JP2015528814A - Compound - Google Patents

Abstract

The present invention relates to new derivatives of 5-aminolevulinic acid (5-ALA) and their use as photosensitizers. Specifically, the compounds of general formula I and their pharmaceutically acceptable salts, methods for preparing such compounds, and their medical and cosmetic properties, for example in photodynamic therapy and diagnostic methods For general applications, wherein R 1 represents a hydrogen atom or an optionally substituted alkyl or cycloalkyl group, and R 2 represents a hydrogen atom or an optionally substituted alkyl group, each of which is the same Or X may be a linking group. [Chemical 1] [Selected figure] None

Description

  The present invention relates to novel derivatives of 5-aminolevulinic acid (5-ALA) and their use as photosensitizers. Specifically, the compounds of general formula I and their pharmaceutically acceptable salts, methods for preparing such compounds, and their medical and cosmetic properties, for example in photodynamic therapy and diagnostic methods Related to specific applications.

  Photodynamic therapy (PDT) is a technique for treating precancerous lesions, cancer, and non-cancerous diseases. PDT involves the administration of a photosensitizer or precursor thereof (ie, a “photosensitizer”) to a target area. The photosensitizer or its precursor is taken up into the cell, where the precursor of the photosensitizer is converted into a photosensitizer. By exposing the target region to light, the photosensitizer is normally excited from the ground singlet state to the excited singlet state. Thereafter, it undergoes an intersystem crossing into a long-lived excited triplet state. One of several chemical species present in the ground triplet state tissue is molecular oxygen. When the photosensitizer and the oxygen molecule are close to each other, energy transfer that the photosensitizer relaxes to its ground singlet state occurs, and an oxygen molecule in an excited singlet state can be created. Singlet oxygen is a very aggressive chemical species that reacts very rapidly with all nearby biomolecules. Ultimately, these destructive reactions kill cells by apoptosis or necrosis, thereby selectively killing, for example, cancer cells. This mechanism is not yet fully understood, but studies suggest that clinical outcome (ie, selectivity for cancerous cells) is not due to selective uptake by cancerous cells. Rather, the level of uptake in all cell types is similar, but the process of conversion and elimination differs in malignant cells and generally metabolically active cells (eg, inflammatory or infected cells) and is normal to cancerous tissue. A concentration gradient is created between the tissues.

  Several photosensitizers, including 5-aminolevulinic acid (5-ALA), both of which are precursors of photosensitizers, and certain derivatives thereof, such as 5-ALA esters, are known and documented in the literature. Have been described. These are converted into protoporphyrins such as protoporphyrin IX (PpIX) which is a photosensitizer in the cell. Currently, several pharmaceutical products containing 5-ALA or its esters are in clinical use in PDT and photodynamic diagnosis (PDD). One of them is Metvix®, which is a cream form dermal product containing 5-ALA methyl ester for photodynamic treatment of actinic keratosis and basal cell carcinoma ( Developed by Photocure ASA, Norway and currently sold by Galderma, Switzerland.) The other is Levlan Kelastick (R) (DUSA Pharmaceuticals, Canada), a product for photodynamic treatment of actinic keratosis containing 5-ALA. Hexvix® (developed by Photocure ASA) is an aqueous solution containing 5-ALA hexyl ester for instillation into the bladder for the diagnosis of bladder cancer.

  However, there remains a need for alternative photosensitizers or precursors thereof. The present invention addresses this need by providing photosensitizer precursors according to the following general formula:

  Thus, as seen from the first aspect, the present invention provides a compound of general formula I, or a pharmaceutically acceptable salt thereof,

Where
R ¹ represents a hydrogen atom or an optionally substituted alkyl or cycloalkyl group;
R ² may be the same or different and each represents a hydrogen atom or an optionally substituted alkyl group;
X is a linking group.

Figure 2 shows fluorescence from skin of minipigs after application of a cream formulation of carboxymethyl 5-amino-4-oxopentanoate hydrobromide. Incubated with carboxymethyl 5-amino-4-oxopentanoate hydrobromide and 2-carboxyethyl 5-amino-4-oxopentanoate hydrobromide by photodynamic action. Shows delayed growth of Aureus bacteria.

In compounds of formula I, the —X—CO ₂ R ¹ moiety is preferably essentially hydrophilic. The term “hydrophilic” means that the —X—CO ₂ R ¹ portion of the molecule tends to interact with or be dissolved by water or other polar solvents and / or substances. The hydrophilic nature of this part of the molecule can be attributed to the nature of the X group and / or the nature of the —CO ₂ R ¹ group. Thus, either X may be hydrophilic, the —CO ₂ R ¹ group may be hydrophilic, or both X and —CO ₂ R ¹ groups may be hydrophilic.

In the first embodiment, only the -X-CO ₂ linking group R ¹ moiety X in the compound of general formula I is hydrophilic.

  A typical example of a hydrophilic group X is one that carries one or more substituents (ie, pendant groups) that impart hydrophilicity to the group, ie, a hydrophilic substituent. The term “hydrophilic substituent” refers to a substituent capable of hydrogen bonding. Typical and preferred hydrophilic substituents are hydroxyl, thiol, carboxyl, carbamoyl, ester, and amine, more preferably hydroxyl, amine, and thiol. Alternatively, the hydrophilic group X may contain one or more heteroatoms that impart hydrophilicity to the group, i.e. heteroatoms capable of hydrogen bonding. Preferred heteroatoms are oxygen or sulfur.

Particular examples of hydrophilic groups X include alkylene groups interrupted by one or more heteroatoms, preferably one or more oxygen atoms. Such groups include polyethylene glycol groups, preferably polyethylene glycol groups containing 1 to 4 ethylene oxide units. Other examples of hydrophilic groups X are alkylene groups, preferably C _1-4 alkylene groups, which contain one or more hydroxyl, thiol, or amine substituents.

When only X is hydrophilic, the R ¹ group may be an optionally substituted alkyl group, ie a linear or branched alkyl group or a cycloalkyl group. When R ¹ is substituted, it is substituted with one or more non-hydrophilic substituents. The term “non-hydrophilic substituent” means a substituent that is essentially incapable of hydrogen bonding. Non-hydrophilic substituents do not include any of the groups described herein as examples of hydrophilic groups, such as hydroxyl, thiol, carboxyl, carbamoyl, ester, and amine. Preferred non-hydrophilic substituents are halo, preferably F or Cl, nitro, and aryl. When the non-hydrophilic substituent is an aryl group, the aryl group can be substituted with one or more halo, alkyl, haloalkyl, alkoxy (eg, C _1-3 alkoxy), or nitro group.

In one embodiment, R ¹ is an unsubstituted linear or branched alkyl group, or an unsubstituted cycloalkyl group, preferably 4-20 carbon atoms (preferably 4-10 carbons). An unsubstituted linear alkyl group containing, for example, 4-8 carbons), 4-20 carbon atoms (preferably 4-10 carbons, such as 4-8 carbons). An unsubstituted branched alkyl group or an unsubstituted cycloalkyl group containing 3 to 7 carbon atoms (preferably 3 to 6 carbon atoms).

When R ¹ is an unsubstituted alkyl group, an R ¹ group that is a linear alkyl group is preferred. A C _4-10 linear alkyl group is more preferable, and a C _4-8 linear alkyl group is most preferable. Representative examples of such groups are n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl. Particularly preferred are n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl.

When R ¹ is an unsubstituted branched alkyl group, such a branched alkyl group is preferably 4-20 carbon atoms, more preferably 4-10 carbon atoms, most preferably Contains 4 to 8 carbon atoms. Representative examples of such branched alkyl groups include sec-butyl, tert-butyl, 2-methylbutyl, 3,3-dimethyl-1-butyl, and 1-ethylbutyl. Preferred groups include sec-butyl and tert-butyl.

When R ¹ is an unsubstituted cycloalkyl group, such cycloalkyl group preferably consists of 3 to 6 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, or cyclohexyl.

When R ¹ is a substituted alkyl group, this is a linear or branched alkyl bearing one or more non-hydrophilic substituents, preferably one or two non-hydrophilic substituents Alternatively, it may be a cycloalkyl group. When two or more non-hydrophilic substituents are present, these may be the same or different. Preferred non-hydrophilic substituents are halo, preferably F or Cl, nitro, and aryl. When the non-hydrophilic substituent is an aryl group, the aforementioned aryl group can be substituted with one or more halo, alkyl, haloalkyl, alkoxy (eg, C _1-3 alkoxy), or nitro group. Preferred such R ¹ groups are C _1-2 alkyl substituted by one or more aryl groups, preferably one or two aryl groups, where the aryl group itself is alkyl (eg, C _{1- 4} alkyl), optionally substituted by halo, nitro, haloalkyl, or alkoxy (eg, C _1-3 alkoxy). Examples of such R ¹ groups are benzyl, 4-isopropylbenzyl, 4-methylbenzyl, 2-methylbenzyl, 3-methylbenzyl, 4- [t-butyl] benzyl, 4- [trifluoromethyl] benzyl. 4-methoxybenzyl, 3,4- [di-chloro] benzyl, 4-chlorobenzyl, 4-fluorobenzyl, 2-fluorobenzyl, 3-fluorobenzyl, 2,3,4,5,6-pentafluorobenzyl , 3-nitrobenzyl, 4-nitrobenzyl, 2-phenylethyl, 4-phenylbutyl, and 4-diphenyl-methyl. More preferred such R ¹ groups are benzyl, 4-isopropylbenzyl, 4-methylbenzyl, 4-nitrobenzyl, and 4-chlorobenzyl. Most preferred is benzyl.

In the second embodiment, only the —CO ₂ R ¹ group present in the —X—CO ₂ R ¹ moiety of the compound of general formula I is a hydrophilic group. A typical and preferred example of such a group is —CO ₂ H, ie when R ¹ represents a hydrogen atom. An alternative preferred example is a —CO ₂ R ¹ group, wherein R ¹ is a short linear or branched alkyl group, preferably 1 to 1 such as methyl, ethyl, n-propyl, and isopropyl. An alkyl group containing 3 carbon atoms.

  In the second embodiment described herein, the linking group X is preferably a linear or branched alkylene group, cycloalkylene group optionally substituted by one or more non-hydrophilic substituents. , An arylene group, or an aralkylene group.

  When X is a linear alkylene group, this is preferably 1 to 16 carbon atoms, ie methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene. , Tridecylene, tetradecylene, pentadecylene or hexadecylene, more preferably 1 to 6 carbon atoms, i.e. methylene, ethylene, propylene, butylene, pentylene or hexylene, even more preferably 1 to 4 carbon atoms, That is, it consists of methylene, ethylene, propylene, or butylene.

  When X is a branched alkylene group, this preferably consists of 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms. Preferred examples are methyl-methylene, dimethyl-methylene, 1-methyl-ethylene, 2-methyl-ethylene, 1,2-dimethylethylene, ethyl-methylene, isopropyl-methylene, 1-ethyl-ethylene, and 2-ethyl- Ethylene. The most preferred examples are methyl-methylene, ethyl-methylene, and isopropyl-methylene.

  When X is a cycloalkylene group, this preferably consists of 3 to 8 carbon atoms, more preferably 5 or 6 carbon atoms. Preferred examples are cyclopentylene and cyclohexylene.

When X is an arylene group, this preferably consists of 6 to 12 carbon atoms. Preferred groups are phenylene, i.e., preferably, _-C 6 _{H 4} having a free valence on a carbon atom 1 and 4 - is.

When X is an aralkylene group, this preferably consists of 7 to 15 carbon atoms. A preferred group is benzylene, ie, —CH ₂ —C ₆ H ₄ —, which preferably has a free valence at carbon atom 4 of the aromatic ring.

  Any of the aforementioned X groups, i.e., linear or branched alkylene groups, cycloalkylene groups, arylene groups, or aralkylene groups, are described in one or more non-hydrophilic substituents, e.g., as described herein. Optionally substituted by any of such groups.

In a third embodiment of the present invention, both of _-CO 2 ^{R 1} groups X and _-X-CO 2 ^{R 1} moiety of the compound of the general formula I is hydrophilic. Typical and preferred examples of such hydrophilic groups X and —CO ₂ R ¹ are provided in the previous paragraph above.

R ² represents a hydrogen atom or an optionally substituted alkyl group (preferably C _1-6 alkyl, eg, C _1-3 alkyl group), each of which may be the same or different. . When R ² is an optionally substituted alkyl group, the substituent may be a hydrophilic substituent or a non-hydrophilic substituent as defined herein.

Preferred compounds according to the invention are those in which at least one R ² represents a hydrogen atom. In a preferred embodiment, each R ² represents a hydrogen atom.

In a preferred embodiment, the present invention provides a compound of general formula I, or a pharmaceutically acceptable salt thereof, wherein
R ¹ is a hydrogen atom or a short linear or branched alkyl group, preferably a linear or branched group containing 1 to 3 carbon atoms such as methyl, ethyl, n-propyl, or isopropyl. Represents an alkyl group.
R ² represents a hydrogen atom or an optionally substituted alkyl group, preferably hydrogen, each of which may be the same or different,
The linking group X is
(A) an optionally substituted C _1-6 alkylene group, or (b) an optionally substituted cycloalkylene, arylene, or aralkylene group.

In a more preferred embodiment, the present invention provides a compound of general formula I, or a pharmaceutically acceptable salt thereof, wherein
R ¹ and R ² each represent a hydrogen atom;
The linking group X is
(A) an optionally substituted C _1-6 alkylene group, or (b) an optionally substituted cycloalkylene, arylene, or aralkylene group.

In a more preferred embodiment, the present invention provides a compound of general formula I, or a pharmaceutically acceptable salt thereof, wherein
R ¹ is a hydrogen atom or a short linear or branched alkyl group, preferably a linear or branched group containing 1 to 3 carbon atoms such as methyl, ethyl, n-propyl, or isopropyl. Represents an alkyl group.
R ² represents a hydrogen atom or an optionally substituted alkyl group, preferably hydrogen, each of which may be the same or different,
The linking group X is
(A) an optionally substituted linear C _1-4 alkylene group, or an optionally substituted branched C _2-6 alkylene group, or (b) an optionally substituted C _5-6 cycloalkylene group. , An optionally substituted C _6-12 arylene group, or an optionally substituted C _7-15 aralkylene group.

In a more preferred embodiment, the present invention provides a compound of general formula I, or a pharmaceutically acceptable salt thereof, wherein
R ¹ and R ² each represent a hydrogen atom;
The linking group X is
(A) an optionally substituted linear C _1-4 alkylene group, or an optionally substituted branched C _2-6 alkylene group, or (b) an optionally substituted C _5-6 cycloalkylene group. , An optionally substituted C _6-12 arylene group, or an optionally substituted C _7-15 aralkylene group.

  In one embodiment, such X groups may be unsubstituted. Alternatively, such groups can be substituted with one or more non-hydrophilic substituents as described above. When the linking group X is substituted, it can be substituted with one or more non-hydrophilic substituents. When two or more substituents are present, they may be the same or different and may be on the same or different carbon atoms of the alkylene chain, cycloalkylene ring, arylene ring, or chain or ring of the aralkylene group. Can be combined.

In one embodiment, the linking group X is an unsubstituted linear C _1-6 alkylene group. Examples of such groups are unsubstituted linear C ₁ alkylene groups, ie methylene groups, unsubstituted linear C ₂ alkylene groups, ie ethylene groups, unsubstituted linear C ₃ alkylene groups. That is, a propylene group, an unsubstituted linear C ₄ alkylene group, that is, a butylene group, an unsubstituted linear C ₅ alkylene group, that is, a pentylene group, and an unsubstituted linear C ₆ alkylene group, That is, it is a hexylene group. Preferred linking groups X are unsubstituted linear C _1-4 alkylene groups, ie methylene, ethylene, propylene, and butylene.

In another embodiment, the linking group X is substituted linear C _1-6 alkylene group, preferably substituted linear C _1-4 alkylene groups, C more preferably, substituted _{1- 2 is an} alkylene group. Preferred substituents are halo, preferably F and Cl and aryl. When the optional substituent is an aryl group, the aryl can be unsubstituted or substituted by one or more halo, alkyl, haloalkyl, alkoxy (eg, C _1-3 alkoxy), or nitro groups. In a preferred embodiment, the aforementioned aryl group is unsubstituted. One or more (eg, one or two) of such substituents can be attached to the alkylene chain. When two or more such substituents are present, they can be linked to the same carbon atom present in the linking group X or to different carbon atoms. In one embodiment, two halo substituents can be linked to the same carbon atom. A mono- or di-fluorinated linear C _1-6 alkylene group, more preferably a linear C _1-4 alkylene group, even more preferably a linear C _1-2 alkylene group is Forms a preferred embodiment of the invention. An aryl substituent, preferably a linear C _1-6 alkylene group substituted by phenyl, more preferably a linear C _1-4 alkylene group, even more preferably a linear C _1-2 alkylene group Form another preferred embodiment of the present invention.

In yet another embodiment, the linking group X is an unsubstituted branched C _2-6 alkylene group. Preferred examples of such X groups are methyl-methylene, ie —CH (CH ₃ ) —, ethyl-methylene, ie —CH (CH ₂ CH ₃ ) —, and isopropyl-methylene, ie CH (CH - _{(CH 3) 2)} - a.

In yet another embodiment, the linking group X is a substituted branched C _2-6 alkylene group. Preferred substituents are halo, preferably F and Cl and aryl. Where the optional substituent is any aryl group, the aforementioned aryl can be unsubstituted or substituted by one or more halo, alkyl, haloalkyl, alkoxy (eg, C _1-3 alkoxy), or nitro groups. In a preferred embodiment, the aforementioned aryl is unsubstituted. Halo is a preferred substituent and one or more of such substituents can be attached to a branched alkylene chain. When two or more such substituents are present, they can be linked to the same carbon atom or different carbon atoms present in the branched alkylene chain. A preferred example of such an X group is trifluoromethyl-methylene.

  In yet another embodiment, the linking group X is an unsubstituted cycloalkylene group such as cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene, cycloheptylene, or cyclooctylene. Preferably, the linking group X is an unsubstituted cycloalkylene group consisting of 5 or 6 carbon atoms, ie cyclopentylene or cyclohexylene.

In yet another embodiment, the linking group X is an unsubstituted arylene group consisting of 6 or 12 carbon atoms. A preferred linking group X in this embodiment is phenylene, ie, preferably —C ₆ H ₄ — having free valences on carbon atoms 1 and 4.

  In yet another embodiment, the linking group X is a substituted arylene group, in which case the arylene group consists of 6 or 12 carbon atoms, preferably 6 carbon atoms. Preferred ring substituents are alkyl, halo, and nitro. One or more (eg, one or two) of such substituents can be attached to the arylene ring.

In yet another embodiment, the linking group X is an unsubstituted aralkylene group consisting of 7-11 carbon atoms. A preferred linking group X in this embodiment is benzylene, ie, preferably —CH ₂ —C ₆ H ₄ —, which has a free valence at carbon atom 4 of the aromatic ring.

Preferred examples of X _{groups, -CH 2 -, - CH 2} CH 2 -, - CH 2 CH 2 CH 2 -, - CH (CH 3) -, - CF 2 -, cyclohexylene, _-CH 2 -C ₆ H ₄ -, - phenylene -, and -CH (Ph) - including (where, Ph = phenyl).

Preferred compounds of the invention are short straight-chain or branched, wherein X represents a group as described above and R ¹ contains a hydrogen atom or ¹ to 3 carbon atoms such as methyl, ethyl, n-propyl and isopropyl. It includes a branched alkyl group, preferably an alkyl group, wherein each R ² is the same and represents hydrogen.

Particular mention may be made of the following which represent preferred compounds according to the invention:
Carboxymethyl 5-amino-4-oxopentanoate

  2-carboxyethyl 5-amino-4-oxopentanoate

  3-carboxypropyl 5-amino-4-oxopentanoate

  Carboxydifluoromethyl 5-amino-4-oxopentanoate

  1-carboxyethyl 5-amino-4-oxopentanoate

  1- (Isopropylcarboxy) ethyl 5-amino-4-oxopentanoate

  (4-Carboxyphenyl) methyl 5-amino-4-oxopentanoate

  Carboxyphenylmethyl 5-amino-4-oxopentanoate

  4-carboxybutyl 5-amino-4-oxopentanoate

  5-carboxypentyl 5-amino-4-oxopentanoate

  7-carboxyheptyl 5-amino-4-oxopentanoate

  8-Carboxyoctyl 5-amino-4-oxopentanoate

  9-carboxynonyl 5-amino-4-oxopentanoate

  10-carboxydecyl 5-amino-4-oxopentanoate

  11-carboxyundecyl 5-amino-4-oxopentanoate

And 15-carboxypentadecyl 5-amino-4-oxopentanoate

  As well as their pharmaceutically acceptable salts.

  As used herein, the term “alkyl” refers to a saturated hydrocarbon group, unless otherwise stated, and is intended to encompass any long or short chain, straight chain and branched alkyl group. .

  As used herein, the term “alkylene” refers to a divalent radical derived from an alkane whose free valence forms a single bond with the rest of the molecule. The term includes straight chain and branched alkylene groups.

  As used herein, the term “cycloalkylene” refers to a divalent radical derived from a cycloalkane whose free valence forms a single bond with the rest of the molecule.

  As used herein, the term “aryl” is intended to encompass aromatic ring systems. Such ring systems may be monocyclic or polycyclic (eg, bicyclic) and contain at least one unsaturated aromatic ring. If they contain polycyclic rings, they can be fused.

  As used herein, the term “arylene” refers to a divalent radical whose free valence is derived from an aromatic hydrocarbon that forms a single bond with the rest of the molecule.

  As used herein, “aralkylene” refers to an alkyl or alkyl substitution that is aryl substituted at a single free valence in both the aryl and alkyl portions of the molecule where the free valence forms a single bond with the rest of the molecule. Refers to a divalent radical derived from a substituted aryl.

  Unless otherwise stated, the term “halo” or “halogen atom” includes fluoro, chloro, bromo, and iodo.

The compounds of the invention may be provided in the form of a free amine, for example, —NH ₂ , —NHR ² , or —NR ² R ² , or preferably a pharmaceutically acceptable salt. Such salts are preferably acid addition salts with pharmaceutically acceptable organic or inorganic acids.

  Suitable acids are, for example, hydrochloric acid, nitric acid, hydrobromic acid, phosphoric acid, sulfuric acid, sulfonic acid and sulfonic acid derivatives, acetic acid, lactic acid, citric acid, tartaric acid, succinic acid, maleic acid, fumaric acid, ascorbic acid, Contains oleic acid as well as stearic acid. Thus, suitable salts are, for example, hydrochloride, hydrobromide, nitrate, phosphate, sulfate, sulfonate, mesylate, tosylate, napsylate, acetate, lactate, citric acid Salts, tartrate, succinate, maleate, fumarate, ascorbate, oleate, and stearate. Preferred acids are hydrochloric acid (HCl) and hydrobromic acid (HBr). Further preferred acids are nitric acid, sulfonic acid, and sulfonic acid derivatives (eg, methanesulfonic acid, naphthalenesulfonic acid, described in International Publication No. WO 2005/092838 of Photocure ASA, the entire contents of which are incorporated herein by reference. Or toluenesulfonic acid).

  The term “pharmaceutically acceptable salt” means a salt that is suitable for use in a pharmaceutical product and meets, for example, safety, bioavailability, and tolerability requirements (eg, P (See H. Stahl et al. (Eds.) Handbook of Pharmaceutical Salts, Publisher Helvetica Chimica Acta, Zurich, 2002).

The compounds of the present invention can be prepared using standard processes and procedures well known in the field of derivatization of polyfunctional compounds, such as derivatization of carboxylic acids. As is known in the art, such reactions involve the protection and deprotection of appropriate groups so that only the required groups remain active and participate in the reaction under selected reaction conditions. Can accompany. Thus, for example, substituents present on any of the reactants used to prepare the compounds according to the invention can be protected. Similarly, the —NR ₂ ² group can be protected during the reaction and then deprotected. Such protection / deprotection procedures are well known in the art and are described, for example, in McOmie in “Protective Groups in Organic Chemistry”, Plenum, 1973 and T.M. W. Greene in “Protective Groups in Organic Chemistry”, Wiley-Interscience, 1981. Please refer to.

  In a further aspect, the present invention thus provides a process for preparing a compound of the invention comprising derivatizing a carboxylic acid group of 5-aminolevulinic acid or a protected derivative thereof.

Thus, the present invention can be viewed as providing a process for preparing the compounds of the present invention, the foregoing process comprising the following steps:
(A) Formula II:

Wherein each R ² ′, which may be the same or different, is an R ² group as defined herein, or a protected derivative thereof,
Formula III:

In which X is as defined herein;
L represents a leaving group, for example, a halogen atom,
R ¹ ′ is a R ¹ group as defined herein, or a protected derivative thereof)
(B) deprotecting a protected derivative of the compound of formula I, and (c) converting at least one of the compounds of formula I into a pharmaceutically acceptable salt thereof.

  The reaction of step (a) is conveniently carried out in a solvent or mixture of solvents such as water, acetone, ethyl acetate, diethyl ether, methylformamide, tetrahydrofuran, etc., at a temperature up to the boiling point of the mixture, preferably at ambient temperature. Can do. The exact conditions of the reaction will depend on the reactants used, and the conditions can be selected to obtain the maximum yield of the final product.

  The reaction of step (a) can conveniently be carried out in the presence of a catalyst, for example an acid binder such as an inorganic or organic acid, or a base.

  The compounds used as starting materials are known from the literature and in many cases are commercially available or can be obtained using methods known per se. For example, 5-ALA is available from Sigma-Aldrich or Biosynth AG, Switzerland.

  The compounds of the invention are preferably in the form of pharmaceutically acceptable and / or skin compatible salts. Such salts are preferably acid addition salts comprising the physiologically acceptable organic or inorganic acids mentioned above.

  The compounds of the present invention are precursors of photosensitizers, that is, they are taken up by cells and converted to protoporphyrin, a photosensitizer. Thus, the compounds of the present invention provide valuable pharmacological properties, ie photosensitizers that impart them useful in photodynamic therapy and photodynamic diagnostic methods, and photodynamic cosmetic methods. As a precursor.

  Accordingly, a further aspect of the present invention is a compound of Formula I as described herein, or a pharmaceutically acceptable salt thereof, together with at least one pharmaceutically acceptable or cosmetically acceptable carrier or excipient. A composition comprising an acceptable salt is provided.

  In a preferred embodiment, the invention provides a pharmaceutical comprising a compound of Formula I as described herein, or a pharmaceutically acceptable salt thereof, together with at least one pharmaceutically acceptable carrier or excipient. A composition is provided.

  In another preferred embodiment, the present invention provides a compound of formula I as described herein, or a pharmaceutically acceptable cosmetic composition thereof, together with at least one cosmetically acceptable carrier or excipient. I will provide a.

  In a further aspect, the present invention is for use as a medicament, for example in a method of photodynamic therapy or photodynamic diagnosis, in particular, on the external or internal surface of the body in response to photodynamic therapy or diagnosis. Provided is a compound or pharmaceutical composition described herein for the treatment or diagnosis of a disorder or an abnormality.

  In yet a further aspect, the invention provides for use in the preparation of a pharmaceutical composition for use in a method of photodynamic therapy or for use in a method of photodynamic diagnosis, specifically A compound of formula I as described herein for use in the preparation of a pharmaceutical composition for the treatment or diagnosis of external or internal surface disorders or abnormalities in response to photodynamic therapy or diagnosis; Or the use of a pharmaceutically acceptable salt is provided.

  Photodynamic treatment or diagnosis of cancer-related infections such as cancer, viral infection (eg, human papillomavirus, hepatitis B, or Epstein Barr virus), or bacterial infection (eg, Helicobacter pylori infection), or non-cancerous The use of the compounds and pharmaceutical compositions described herein in the treatment or diagnosis of a condition forms a preferred embodiment of the present invention.

  As used herein, the terms “cancer” and “cancerous” are used in reference to a condition in which malignant cells are present. Thus, premalignant conditions are not encompassed by these terms.

  The term “non-cancerous” includes benign and pre-malignant conditions.

  As used herein, the term “treatment” or “therapy” encompasses curative as well as prophylactic treatment or therapy.

  Abnormalities and disorders that can be treated or diagnosed by the present invention include any malignant, pre-malignant, and benign abnormalities that respond to photodynamic therapy or diagnosis.

  In general, cells that are metabolically active respond to photodynamic therapy or diagnosis using the compounds of the present invention. An example of a metabolically active cell is a cell that undergoes an abnormal growth pattern. Such abnormal growth patterns include increased cell number / increased cell proliferation (hyperplasia), abnormal maturation and differentiation of cells (dysplasia), and abnormal proliferation of cells (neoplasia). Hyperplastic cells still undergo normal regulatory control mechanisms. Neoplastic cells are genetically abnormal cells that proliferate in a non-physiological manner that does not respond to normal stimuli. Another example of a metabolically active cell is an inflammatory cell.

  The compounds and pharmaceutical compositions according to the invention are particularly suitable for use in photodynamic treatment and diagnosis of neoplasms and tumors (benign, premalignant and malignant) on internal and external body surfaces (eg skin). Is suitable. Examples of such neoplasms and tumors on external body surfaces are actinic keratosis and Bowen's disease. Examples of neoplasms and tumors on the internal body surface are bladder cancer and colon cancer.

  In addition, the compounds and pharmaceutical compositions according to the invention comprise acne (associated with Propionibacterium acnes bacteria), sputum or cervical intraepithelial neoplasia (associated with human papillomavirus), gastric cancer (associated with Helicobacter pylori bacteria) ), And photodynamic therapy and diagnosis of diseases and disorders associated with viral, bacterial, and fungal infections such as pseudomembranous enteritis (Clostridial difficile bacteria).

  Furthermore, the compounds and pharmaceutical compositions according to the invention are particularly suitable for use in the photodynamic treatment of infections of skin or wounds with Gram positive bacteria. Such infections are often caused by Staphylococcus aureus (S. aureus) and are generally treated with antibiotics such as penicillin. Many Staphylococcus aureus strains have developed antibiotic resistance, which does not meet the medical need to seek alternative treatments. Other Gram-positive bacteria involved in bacterial wound infection are, for example, Staphylococcus epidermidis, Bacillus butyls, Enterococcus ficarias, and Micrococcus luteus.

  In addition, the compounds and pharmaceutical compositions according to the invention are particularly suitable for use in the photodynamic treatment and diagnosis of inflammatory cells. Cellular inflammation is usually an attempt to protect by organisms that remove noxious stimuli and initiate the healing process and is therefore often associated with infection. Examples include inflammatory acne, colitis (eg, inflammatory bowel disease, ulcerative colitis, and Crohn's disease), and infectious dermatitis, ie, skin inflammation caused by bacterial, viral, or fungal infection It is.

  Internal and external body surfaces that can be treated according to the present invention include, for example, mucous membranes, organ linings such as the respiratory, gastrointestinal, and genitourinary glands, and glands with conduits that move onto such surfaces (eg, liver, sebaceous glands). Including the skin (including follicles, mammary glands, salivary glands, and seminal vesicles) and all other epithelial and serosal surfaces. In addition to the skin, such surfaces include, for example, the lining of the vagina, the endometrium, and the urothelium. Such surfaces may also include cavities formed in the body after excision of a lesion or cancerous tissue, eg, brain cavities after excision of a tumor such as a glioma.

  Thus, exemplary surfaces are (i) skin and conjunctiva, (ii) oral cavity, pharynx, esophagus, stomach, intestine, and intestinal appendages, rectum, and inner lining of anal canal, (iii) nostril, sinus, upper Inner lining of pharynx, trachea, bronchi and bronchiole, (iv) inner lining of ureter, bladder and urethra, (v) inner lining of vulva, vagina, cervix, and uterus, (vi) parietal and visceral pleura , (Vii) the inner layers of the peritoneum and pelvic cavities, and the surface of the organs contained within these cavities, and (viii) the dura mater and meninges.

  In order to obtain a pharmaceutical composition according to the invention, the compound according to formula I can be prepared according to any conventional method according to techniques well known in the art, using one or more physiologically acceptable carriers or excipients. May be formulated in a manner. Where appropriate, the compounds or compositions according to the present invention may, for example, be provided before or after the addition of a carrier or excipient, for example, gamma irradiation, autoclaving, or heat sterilization, to provide a sterilized formulation. Is sterilized by

  The pharmaceutical composition can be administered systemically (eg, orally or parenterally) or locally (eg, by injection or topical) at or near the affected site. Topical pharmaceutical compositions are preferred, any of gels, creams, ointments, sprays, lotions, salves, sticks, powders, suppositories, suppositories, aerosols, drops, solutions, and other conventional pharmaceutical forms in the art. Including Local administration to inaccessible sites can be accomplished by techniques known in the art, for example, using a catheter or other suitable drug delivery system.

  Ointments, gels, and creams can be formulated with an aqueous or oily base, for example, by adding suitable thickening agents and / or gelling agents. Any thickening or gelling agent used should be devoid of non-toxic, non-irritating and leaching impurities. They should be inert to the active ingredient, i.e. not promote its degradation. Formulations for wound treatment, eg treatment of bacterially infected wounds, can be based on gel formulations, eg hydrogels. The compounds of the present invention can be incorporated into such hydrogel formulations. Alternatively, the compounds can be incorporated into liposomes that are incorporated into hydrogels (see, eg, J. Hurler et al., J. Pharm. Sci. 101, No. 10, 2012, 3906-3915). Lotions are formulated with an aqueous or oily base and will in general also contain one or more emulsifying agents, dispersing agents, suspending agents, thickening agents, or coloring agents. The powder can be formed using any suitable powder base. Drops, sprays, and solutions can be formulated with aqueous or non-aqueous bases that also contain one or more dispersants, solubilizers, or suspending agents. Aerosol sprays are conveniently delivered from pressurized packs by using suitable propellants.

  Alternatively, the pharmaceutical composition can be provided in a form suitable for oral or parenteral administration, eg, by intradermal, subcutaneous, intraperitoneal, or intravenous injection. Thus, alternative pharmaceutical forms include corn starch, lactose, sucrose, microcrystalline cellulose, magnesium stearate, polyvinyl pyrrolidone, citric acid, tartaric acid, water, water / ethanol, water / glycerol, water / sorbitol as carriers or excipients Uncoated or coated tablets, capsules, suspensions, containing fatty substances such as water / polyethylene glycol, propylene glycol, stearyl alcohol, carboxymethyl cellulose, or hard fat, or suitable mixtures thereof, And a solution. Where the pharmaceutical composition according to the present invention optionally comprises one or more pharmaceutically acceptable solvents, such solvents may be free fatty acids, free fatty alcohols, aqueous solutions such as buffers, or water. There may be.

  The pharmaceutical composition comprises a lubricant, a thickener, a wetting agent, an emulsifier, a suspending agent, a preservative, a filler, a binder, a preservative, an adsorption enhancer, such as a surface penetrant described below, etc. Conventional pharmaceutical excipients may additionally be included. Solubilizing and / or stabilizing agents such as cyclodextrins (CD) α, β, γ, and HP-β cyclodextrins may also be used. Those skilled in the art will be able to select suitable excipients based on their purpose. Common excipients that can be used in the pharmaceutical products described herein are various handbooks (eg, DE Bugay and W. P. Findlay (Eds) Pharmaceutical exciients (Marcel Dekker, New York, 1999), E-M Hoepfner, A. Reng and PC Schmidt (Eds) Fielder Encyclopedia of Excitients for Pharmaceuticals, Ceramics and Related Aids. der Hilfstoffe fur Pharmazie, Kosmet k und angrenzende Gebiete (Edition Cantor Aulendorf, 1989)) to have been listed.

  All the above-mentioned pharmaceutically acceptable excipients are well known in the art and are commercially available from various manufacturers.

  The pharmaceutical compositions of the invention can be formulated to provide rapid, sustained or delayed release of the active ingredient after administration to a patient by employing procedures well known in the art.

  The concentration of a compound described herein in a pharmaceutical composition will vary or be adjusted depending on the nature of the compound, composition, mode of administration, condition being treated or diagnosed, and the subject to which it is administered. Can be done. However, generally a concentration range of 0.01 to 50% by weight, such as 0.05 to 20% by weight, or 1 to 10% by weight, for example 1 to 5% by weight, is suitable. It will be appreciated that PDT may require higher concentrations of the compounds of the invention used in diagnostic methods.

  In another embodiment, the pharmaceutical composition is described in one or more bioadhesives, eg, Photocure ASA, International Publication No. WO 02/09690, the entire contents of which are incorporated herein by reference. A mucoadhesive agent may further be included.

  The compounds of the present invention may be formulated and / or administered with other active ingredients that function to enhance photodynamic effects, such as surface penetration aids (or penetration enhancers) and / or chelating agents. Suitable surface penetration aids and chelating agents and suitable concentrations of such agents are described in Photocure ASA, International Publication No. WO 2009/074811, the entire contents of which are hereby incorporated by reference. Depending on the nature of the composition, the compounds can be co-administered with any other such agents, eg, in a single composition, or they can be administered separately (eg, sequentially). In some cases, it may be beneficial to pretreat the external or internal surface of the body to be treated with a surface penetration aid in a separate step prior to administering the active ingredient. If a surface penetration aid is used in the pretreatment step, it can be used at higher concentrations, eg up to 100% by weight. When such a pretreatment step is used, the pharmaceutical composition according to the invention can be subsequently administered up to several hours after the pretreatment, for example at intervals of 5-60 minutes after the pretreatment.

  Pharmaceutical compositions described herein as a mixed preparation for simultaneous, separate or sequential use in a method of photodynamic treatment or diagnosis of external or internal surface abnormalities, and optionally surface penetration aids Products and kits containing agents and / or chelating agents form a further aspect of the invention.

Viewed alternatively, this aspect of the invention provides a kit for use in a method of photodynamic treatment or diagnosis of a disease, disorder, or abnormality of an external or internal surface of the body, said kit comprising:
(A) a first container containing a compound described herein, or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition described herein;
(B) a second container containing at least one surface penetration aid, and optionally,
(C) one or more chelating agents contained in either the aforementioned first container or any third container.

  A further aspect of the invention provides a method for photodynamic treatment or diagnosis of a disease, disorder, or abnormality of an external or internal surface of the body, said method comprising a pharmaceutical composition as described herein. Applying to the affected surface and exposing the surface to light.

  After administration of the pharmaceutical composition to the exterior or interior surface of the body, the desired area to be treated or examined (in the case of diagnosis) is exposed (irradiated) to light to achieve the desired photoactivation. . The length of time period between administration and exposure to light, ie the incubation time, depends on the nature of the compound, the nature of the composition, the condition being treated or diagnosed, and the mode of administration. In general, the compounds of the invention in pharmaceutical compositions are sufficiently released to be taken up by cells of the tissue to be treated or diagnosed prior to photoactivation, converted to photosensitizers, It is necessary to achieve an effective tissue concentration at the treatment / diagnosis site being treated. Typically, the incubation time is up to 10 hours, such as about 10 minutes to 10 hours, such as 30 minutes to 7 hours, or 1 hour to 5 hours. Direct topical administration results in shorter incubation times, eg, no incubation time (ie, intermediate exposure to light after administration), about 1 minute to 3 hours, eg, 5 minutes to about 2 hours, or 15 It can be minutes to 1.5 hours, or 30 minutes to 1 hour. If systemic uptake is required after oral administration, the incubation time may be longer, eg, about 30 minutes to 6 hours, eg, 2-5 hours, or 3-4 hours. The optimal incubation time that maximizes the concentration of photosensitizer at the target site can be readily determined, for example, by fluorescence measurements over time.

Irradiation is generally applied at high light intensity, i.e. high fluence rate, for a short time, or at low light intensity, i.e. low fluence rate. The latter may be preferred in the PDT procedure, especially when the patient is not anesthetized. The low light intensity PDT procedure reduces patient discomfort without any reduction in the effectiveness of the treatment. However, if the PDT or PDD procedure is required to anesthetize and / or fixate the patient and / or need to be performed in the operating room, it will be at high light intensity, ie, at a high fluence rate for a short time. The applied irradiation may be preferred. The fluence rate depends on the means of irradiation, ie the specific lamp or laser used. The fluence rate may be an intrinsic parameter that cannot be selected by the lamp / laser user. However, if the fluence rate can be selected, a fluence rate of 0.5 to 100 mW / cm ² can generally be selected for lamps including light emitting diodes. For low fluence rate procedures, fluence rates below 50 mW / cm ² are preferred. A fluence rate in the range of 1 to 30 mW / cm ² is more preferable, and a range of ^{2 to} 10 mW / cm ² is most preferable. For high fluence rate procedures, fluence rates above 50 mW / cm ² are preferred, more preferably in the range of 50-70 mW / cm ² .

  The light wavelength used for irradiation can be selected to achieve the desired photodynamic effect. Irradiation with light wavelengths in the range of 300-800 nm, for example 400-700 nm and 500-700 nm has been found to be particularly effective. For PDT, it may be particularly important to include wavelengths of 630 and 690 nm. Red light (600-670 nm) is particularly preferred because light of this wavelength is known to penetrate well into the tissue. For PDD, the area of interest can be inspected first using white light. For actual photodynamic diagnosis, typically blue light having a wavelength in the range of 360 to 450 nm is commonly used and can be detected or measured visually by a suitable spectrometer (eg, 550-750 nm).

PDT irradiation generally, 10~200J / cm ^2, preferably, 20~100J / cm ^2, most preferably, be applied in light of 25~60J / cm ^2. For PDD, irradiation is preferably performed during the entire diagnostic procedure, or part thereof, for example when combined with white light detection. For both PDT and PDD, a single irradiation can be used, or a light split dose can be used where the light dose is delivered in several fractions, eg, minutes to hours between irradiations. . Multiple irradiations may also be applied.

  The irradiation duration (ie, irradiation time) of PDT depends on the irradiation device and the fluence rate of the desired light dose. In essence, light dose is a product of irradiation time and fluence rate.

  Various irradiation means such as lasers and lamps are known in the art. The latter may be a lamp with a light bulb, for example a short arc xenon bulb or a fluorescent lamp. Alternatively, the lamp can comprise light emitting diodes or organic light emitting diodes (LEDs and OLEDs). An endoscope may be used for irradiation of the inner surface of the body, for example, the lining of the bladder or colon. In general, an endoscope includes an external light source (for example, a laser or a lamp) coupled to an optical fiber that functions as a waveguide for transmitting light from an external light source to a target region.

In a further aspect, the present invention thus provides a method for in vivo imaging of a target site on the internal or external surface of the body, said method comprising the following steps:
(A) administering to a subject, eg, a human or non-human animal, a compound described herein, a pharmaceutically acceptable salt thereof, or a pharmaceutical composition comprising said compound or said salt Steps,
(B) If necessary, the time required for the compound or pharmaceutically acceptable salt thereof to be taken up by the cells at the target site and converted to a photosensitizer to achieve an effective concentration at the target site. Waiting for a period,
(C) exposing the target site to light, thereby photoactivating the photosensitizer;
(D) detecting fluorescence indicating abnormality of the target site;
(E) optionally, converting the detected fluorescence into an image of the target region.

  In a preferred embodiment of this aspect of the invention, the imaging method is performed on a subject pre-administered with a compound as described above, a pharmaceutically acceptable salt thereof, or a pharmaceutical composition comprising the compound or salt as described above. can do.

  The PDD procedure described herein may also be performed during surgery where a compound of the invention or a pharmaceutical composition comprising the aforementioned compound is administered to a patient and the surgery is then performed under blue light. it can. The fact that the anomaly fluoresces under blue light helps the surgeon to define a “surgical boundary”, thereby allowing more selective excision of the desired area (eg, a tumor). The use of the compounds and pharmaceutical compositions described herein in a surgical method forms a further aspect of the invention.

  The treatment and diagnostic methods described herein can also be used in the form of combination treatment. For example, a series of PDTs performed with respect to an abnormality, disorder, or disease of the internal or external surface of the body using a compound or composition described herein may be followed by a PDD method (e.g., To determine the extent to which PDT was effective and / or to detect any recurrence of the condition).

  In a further aspect, the present invention thus provides: (i) performing photodynamic treatment of an abnormality, disorder, or disease on an internal or external surface of a patient's body; and (ii) performing photodynamic diagnosis on said patient. A compound or composition as described herein for use in a method comprising the steps of: At least one of steps (i) and (ii) is performed after administering a compound or pharmaceutical composition according to the present invention to said patient. Preferably, both steps (i) and (ii) are performed after administration of such a compound or composition.

  After using any of the methods described herein to identify abnormalities, disorders, or diseases of the internal or external surface of the body, this can then be done by another treatment, such as surgery or chemistry. Can be treated by treatment. Examples of current treatment include surgical treatment, endoscopic resection, chemical resection, thermal resection, or mechanical resection. In one embodiment of the invention, further application of the compound or pharmaceutical composition to the site of interest can be made to provide PDT.

  The compounds of the invention can also be used in in vitro diagnostic methods, for example for the examination of cells contained in body fluids. High fluorescence associated with metabolically active cells can advantageously represent an abnormality or disorder. This method is sensitive and can be used for the early detection of abnormalities or disorders, such as bladder cancer or lung cancer, by examination of epithelial cells in urine or sputum samples, respectively. Other useful body fluids that can be used for diagnosis in addition to urine and sputum include blood, semen, tears, spinal fluid and the like. Tissue samples or preparations such as biopsy tissue or bone marrow samples can also be evaluated. Thus, the present invention extends to the use of the compounds of the present invention, or pharmaceutically acceptable salts thereof, for photodynamic diagnosis and products and kits for performing the foregoing diagnosis.

A further aspect of the present invention relates to a method for in vitro diagnosis of an abnormality, disorder, or disease of an internal or external surface of a patient's body by assaying said patient fluid or tissue sample, said method comprising: At least the following steps:
i) mixing said sample of bodily fluid or tissue with said compound, a pharmaceutically acceptable salt thereof, or a pharmaceutical composition comprising said compound or said salt;
ii) exposing said mixture to light;
iii) confirming the fluorescence level;
iv) optionally comparing the fluorescence level to a control level.

  The compounds according to the invention are caused by pathogenic fungi, or conditioned pathogenic fungi, i.e. bacteria that are part of the normal human flora, but can be pathogenic under certain conditions, or otherwise. It can also be used for photodynamic treatment of abnormalities, disorders, or diseases of the internal or external surface of the body associated with the method.

  Multidrug resistance is an increasing problem in the field of infectious diseases. Among the many species of pathogens that have become resistant to conventional antibiotics is the cause of skin infection and S. aureus (S. aureus) involved in wound and burn infection. S. toxic strains. Aureus can enter the bloodstream as a result of such an infection, which at the same time is associated with severe complications and even life such as toxemia (toxic shock syndrome), endocarditis, and pneumonia May lead to a condition. S. Aureus resistant strains are methicillin resistant S. cerevisiae. Includes Aureus (MRSA).

  The compounds described herein, when used in PDT, kill bacterial cells, in particular Gram positive bacteria, specifically Staphylococcus aureus, or at least reduce their potential for growth. It was found to be effective.

  Viewed from a further aspect, therefore, the present invention is for use in a method for the treatment and / or prevention of bacterial infections, for example in a method for the treatment or prevention of conditions caused by or associated with drug-resistant bacteria. In order to do so, a compound or pharmaceutical composition as described herein is provided. Methods of medical treatment of such conditions in which an effective amount of the compound or composition is administered to a patient in need thereof form a further aspect of the invention.

  In infants, S. Aureus infection can cause a severe disease, staphylococcal burn-like skin syndrome (SSSS). The disease shows widespread formation of liquid-filled blisters that are thin and easily burst. In addition, S.M. Aureus is prevalent in patients with atopic dermatitis who are less resistant than others. Often cause complications, and the disease is mostly found in reproductive and active places including the axilla, hair, and scalp.

  As mentioned above, the compounds according to the invention are also particularly useful for photodynamic cosmetic methods. Accordingly, in a further aspect, the present invention provides a cosmetic composition comprising a compound of formula I or a pharmaceutically acceptable salt thereof together with at least one skin compatible carrier or excipient.

  As used herein with respect to any composition, product, kit, method, or use, the term “beauty” improves or improves the cosmetic appearance of the skin of the individual who has received it for cosmetic purposes. Or intended to define a product or method of treatment that is used or intended for use.

  The term “skin-compatible” refers to a material suitable for use in a cosmetic skin composition, eg, a composition for use on mammals, specifically human skin. “Skin compatible” carriers or excipients are usually non-irritating and well tolerated.

  To obtain a cosmetic composition according to the present invention, the compound of formula I is formulated in any conventional manner using one or more skin-compatible carriers or excipients according to techniques well known in the art. Can be done. Where appropriate, the compounds of the composition can be sterilized using the methods described above for pharmaceutical compositions.

  Cosmetic compositions are typically applied to the skin. Suitable cosmetic compositions include any of gels, creams, ointments, sprays, lotions, salves, sticks, powders, solutions, and other conventional cosmetic formulations in the art.

  Cosmetic ointments, gels, lotions, salves, and creams can be formulated, for example, with aqueous or oily bases (preferred for ointments and salves) in addition to suitable thickening and / or gelling agents. Any thickening or gelling agent used should be devoid of non-toxic, non-irritating and leaching impurities. They should be inert to the compounds of the present invention, i.e. not promote their degradation. Lotions and creams are formulated with an aqueous or oily base and will in general also contain one or more emulsifying agents, dispersing agents, suspending agents, thickening agents, or coloring agents. The powder can be formed using any suitable powder base. Sprays and solutions can be formulated with aqueous or non-aqueous bases that also contain one or more dispersants, solubilizers, or suspending agents.

  The cosmetic composition may additionally contain conventional cosmetic excipients such as lubricants, thickeners, wetting agents, emulsifiers, suspending agents, preservatives, perfumes, fillers, binders and preservatives. . They can further include surface penetrants and the like described below. Those skilled in the art will be able to select suitable excipients based on their purpose. Common excipients that can be used in the cosmetic products described herein are various handbooks (eg, E-M Hoepfner, A. Reng and PC Schmidt (Eds), Federal Encyclopedia of Excipients for Pharmaceuticals). , Cosmetics and Related Areas (Edition Cantor, Munich, 2002), and HP Fielder (Ed) Lexikon der Hiffssoffer Fermandien Arende 198 Furthermore, skin compatible excipients and carriers for use in cosmetic compositions according to the present invention and suitable amounts thereof are disclosed in International Publication No. WO 2011/107478 of Photocure ASA, the entire contents of which are by reference. Incorporated herein.

  All the above cosmetic excipients are well known in the art and are commercially available from various manufacturers.

The desired amount of the compound of the invention in the cosmetic composition depends on the specific nature of the formulation, whether a light source is used for cosmetic treatment, if so, the type of light source, and the wavelength selected, the duration of the cosmetic treatment Depends on several factors including time, as well as the overall number of treatments. In view of these various factors, the amount can be readily determined by one skilled in the art. Cosmetic compositions according to the present invention are generally 5% by weight or less of a compound of the invention, preferably 0.02 to 3% by weight, more preferably 0.05 to 1.5% by weight, eg 0 0.5 to 1.25% by weight, most preferably 0.1 to 1.0% by weight, most preferably in the range of 0.25 to 0.75% by weight. In determining the desired amount within these ranges, the following criteria within the knowledge and expertise of those skilled in the art may also be considered:
Cosmetics that can penetrate deeper into the skin, for example due to the nature of the composition, the nature of the selected compounds of the invention, or the presence of agents that promote deeper penetration, such as skin penetration enhancers The composition typically contains a lower concentration of a compound of the invention than a composition that tends to remain primarily on the surface of the skin,
Cosmetic compositions intended for long skin treatment durations (ie incubation of longer compositions on the skin and / or longer illumination) are usually less than compositions intended for short treatment durations Containing a compound of
A cosmetic composition intended for two or more skin treatments, eg several or multiple treatments such as several treatments or repeated treatments over a period of time, is usually intended for a single use, or Containing less of the compound of the invention than a composition intended for a limited number of uses, often at intervals between treatments,
A cosmetic composition intended for the treatment of skin with few signs of aging (with light) contains fewer compounds of the invention than a composition intended for the treatment of severe (light) aging skin. obtain.

  The cosmetic composition according to the invention can be used in a method of cosmetic treatment. Such cosmetic treatment can be performed to enhance and / or improve the appearance of the skin of a mammalian subject, preferably a human subject. In particular, signs of aging (by light) can be improved, for example, reducing the appearance of eyelid wrinkles, bears, fine lines, wrinkles, reducing pore size, and improving skin tension and elasticity.

  Suitable light sources for such cosmetic treatments and suitable fluence rates, irradiation times, light doses and wavelengths are disclosed in detail in Photocure ASA International Publication No. WO 2011/107478, the entire contents of which are hereby incorporated by reference. Incorporated in the description.

  The invention is illustrated by the following non-limiting examples and with reference to the accompanying drawings.

FIG. 1 shows fluorescence from skin of minipigs after application of a cream formulation of carboxymethyl 5-amino-4-oxopentanoate hydrobromide.
FIG. 2 Incubated with carboxymethyl 5-amino-4-oxopentanoate hydrobromide and 2-carboxyethyl 5-amino-4-oxopentanoate hydrobromide by photodynamic action S. Shows delayed growth of Aureus bacteria.

The following abbreviations are used in the examples.
Boc-tert-butoxycarbonyl Cbz-carboxybenzyl dec-decomposition
Example 1-Preparation of carboxymethyl 5-amino-4-oxopentanoate hydrohalide (hydrochloride and hydrobromide) 1a-t-butoxycarbonylmethyl 5- (Boc-amino) -4-oxopentano Preparation

Under argon at ambient temperature, triethylamine (2.22 g; 22.0 mmol) was added to t in 5- (Boc-amino) -4-oxopentanoic acid (4.62 g; 20.0 mmol) and ethyl acetate (60 mL). -Added dropwise to a stirred solution of butyl bromoacetic acid (4.30 g; 22.0 mmol). The mixture (slurry) was refluxed for 17 hours, then cooled to ambient temperature, poured into 0.5 M HCl (100 mL) and shaken well. The aqueous portion was extracted with ethyl acetate (2 × 20 mL). The combined organic solution was washed with saturated NaHCO ₃ solution (1 × 20 mL) and saturated NaCl solution (1 × 20 mL), dried (MgSO ₄ ), filtered and evaporated. Evaporation yielded an amber oil that was purified by 40 × 55-mm silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 1) (600 mL) and purified in 5 × 100 mL fractions. Minutes were collected. Evaporation of fractions 1 and 2 gave 6.15 g (89%) of product (yellow oil).

¹ H NMR: (200 MHz; CDCl ₃ ): δ 1.44 (9H, s), 1.47 (9H, s), 2.77 (4H, s), 4.06 (2H, d, J = 4) .8 Hz), 4.49 (2H, s), 5.25 (1H, br s).
¹³ C NMR: (50 MHz; CDCl ₃ ): δ 27.5, 28.0, 28.3, 34.2, 50.3, 61.3, 79.8, 82.5, 155.5, 166. 5, 171.7, 203.9.

  Preparation of 1b-carboxymethyl 5-amino-4-oxopentanoate hydrochloride

  A 4M solution of hydrogen chloride in dioxane (35 mL; 0.14 mol) was added to the product of 1a (3.3 g; 9.5 mmol) and stirred with evolution until the oil dissolved as gas evolved. After standing for 1 hour, the solvent was evaporated, the residue was triturated with diethyl ether (4 × 20 mL) and the oil solidified to a tan powder. The residue was filtered and dried overnight in a dry pistol at 50 ° C. and 13 mm Hg. 2.05 g (96%) of product was obtained (tan powder).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 2.65 (2H, t, J = 6.2 Hz), 2.82 (2H, t, J = 5.9 Hz), 3.96 (2H, br s), 4.57 (2H, s), 8.40 (3H, br s).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 26.7, 34.1, 46.5, 60.7, 168.8, 171.5, 202.3.

  Preparation of 1c-carboxymethyl 5-amino-4-oxopentanoate hydrobromide

  A 30% solution of hydrogen bromide in acetic acid (12 mL) is added to the product of 1a (3.3 g; 9.5 mmol) cooled with an ice bath and stirred until the oil has dissolved, evolving gas. did. After stirring for 15 minutes, the mixture was triturated with hexane (4 × 20 mL) and diethyl ether (4 × 20 mL) to solidify the oil to a tan powder. The residue was filtered and dried overnight in a dry pistol at about 50 ° C. and 12 mm Hg. 4.44 g (92%) of product was obtained (tan brown powder, mp 110-114 ° C. (dec.)).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 2.66 (2H, t, J = 6.6 Hz), 2.85 (2H, t, J = 6.6 Hz), 4.02 (2H, d, J = 4.8 Hz), 4.57 (2H, s), 8.14 (3H, br s).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 26.7, 34.1, 46.6, 60.6, 168.8, 171.5, 202.3.

Example 2-1 Preparation of 1- (isopropylcarboxy) ethyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 2a-benzyl 2-bromopropanoate p-Toluenesulfonic acid monohydrate in 2-bromopropanoic acid (15.3 g; 100 mmol), benzyl alcohol (13.0 g; 120 mmol), and cyclohexane (200 mL) (50 mg) of the mixture was refluxed in a Dean-Stark apparatus for 19 hours. The reaction mixture was cooled to ambient temperature and washed with saturated NaHCO ₃ solution (1 × 30 mL), water (1 × 30 mL), and saturated NaCl solution (1 × 30 mL). After drying, (MgSO ₄ ), filtering and evaporation, the residue was distilled under reduced pressure. 25.4 g (87%) of product was obtained (colorless liquid, bp 111-113 ° C./1.1 mm Hg).

¹ H NMR: (200 MHz; CDCl ₃ ): δ 1.83 (3H, d, J = 7.0 Hz), 4.40 (1H, q, J = 7.0 Hz), 5.20 (2H, s) 7.36 (5H, s).
¹³ C NMR: (50 MHz; CDCl ₃ ): δ 21.6, 39.9, 67.5, 128.0, 128.4, 128.5, 135.0, 169.9.

Preparation of 2b-1- (benzyloxycarbonyl) ethyl 5- (Cbz-amino) -4-oxopentanoate Triethylamine was converted to 5- (Cbz-amino) -4-oxopentanoic acid (4.00 g; 15.0 mmol). ) And the product of 2a (3.65 g; 15.0 mmol) in ethyl acetate (50 mL) was added dropwise. The stirred mixture was refluxed under argon for 2 days. After cooling to ambient temperature, 0.5M HCl solution (50 mL) was added and the mixture was shaken well. The aqueous layer was extracted with ethyl acetate (2 × 20 mL). The combined ethyl acetate was washed with saturated NaHCO ₃ solution (2 × 15 mL) and saturated NaCl solution (1 × 15 mL), then dried (MgSO ₄ ). After filtration and evaporation, it was purified by 60 × 55 mm silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 1) (1000 mL) and 8 × 100 mL fractions were collected amber oil I got a thing. Evaporation of fractions 3-5 gave 4.92 g (77%) of product (oil).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 1.41 (3H, d, J = 7.0 Hz), 2.56 (2H, t, J = 6.3 Hz), 2.68 (2H, 4. t (J = 6.3 Hz), 4.03 (2H, d, J = 7.1 Hz), 5.04 (2H, s), 5.06 (1H, q, J = 6.2 Hz). 16 (2H, s), 7.36 (10H, m), 7.54 (1H, br s).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 16.6, 26.9, 33.5, 49.6, 65.4, 66.1, 68.4, 127.6, 127.8, 128.3, 128.4, 135.6, 137.0, 156.3, 170.1, 171.6, 205.2.

Preparation of 2c-1- (isopropylcarboxy) ethyl 5-amino-4-oxopentanoate hydrochloride Product of 2b (4.92 g; 11.5 mmol), 10% palladium on activated carbon (100 mg), hydrogen gas And a stirred mixture of 2.0 M hydrogen chloride in diethyl ether (10 mL; 20 mmol) in 2-propanol (15 mL) and dioxane (15 mL) was hydrogenated at ambient temperature for 2 days at about 6 bar. The mixture was filtered through a Celite® 545 pad and the residue was washed with 2-propanol (2 × 5 mL). The combined filtrates were evaporated and the resulting oil was triturated with diethyl ether (4 × 10 mL) and then stored in the freezer. The oil did not solidify. After drying in vacuo (0.005 mm Hg) overnight, 1.97 g (71%) of product was obtained (tan, viscous oil).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 1.17 (6H, dd, J = 5.7 Hz), 1.37 (3H, d, J = 7.0 Hz), 2.60 (2H, t, J = 6.2 Hz), 2.80 (2H, t, J = 6.4 Hz), 3.93 (2H, br s), 4.88 (2H, m), 8.38 (3H, br) s).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 16.6, 21.3, 26.8, 34.1, 46.5, 68.5, 68.7, 169.7, 171.5, 202.3.

Example 3-Preparation of carboxydifluoromethyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 3a-benzyl bromodifluoroacetate This compound was prepared according to Example 2a, p- in bromodifluoroacetic acid (9.82 g; 68.7 mmol), benzyl alcohol (7.0 g; 65 mmol), and cyclohexane (120 mL). Prepared from toluenesulfonic acid monohydrate (50 mg). The crude product obtained after evaporation was used as such without further treatment with 3b.

¹ H NMR: (300 MHz; CDCl ₃ ): δ 5.35 (2H, s), 7.39 (5H, s).
¹³ C NMR: (75 MHz; CDCl ₃ ): δ 69.8, 108.8 (t, J _C−F = 312 Hz), 128.6, 128.9, 129.2, 140.8, 159.5 ( t, J _C-F = 31 Hz).

Preparation of 3b- (benzyloxycarbonyl) difluoromethyl 5- (Cbz-amino) -4-oxopentanoate Using a syringe, triethylamine (3.5 mL; 2.5 g; 25 mmol) was added to the crude product of 3a ( 8.6 g; 20 mmol) and to a stirred mixture of 5- (Cbz-amino) -4-oxopentanoic acid (6.63 g; 25 mmol) in dry acetonitrile (100 mL). The mixture was refluxed for 18 hours, then the solvent was evaporated and the dark red residue was dissolved in diethyl ether (100 mL) and 0.5 M HCl (100 mL). After thorough mixing, the ether layer was washed with water (2 × 15 mL), saturated NaHCO ₃ (2 × 15 mL), and saturated NaCl solution (1 × 15 mL), then dried (MgSO ₄ ). After filtration and evaporation, the residue was purified by 60 × 55 mm silica gel 60 column flash chromatography eluting with dichloromethane-diethyl ether (9: 1) (1000 mL) and 10 × 75 mL fractions were collected. After evaporation of fractions 2-5 and vacuum drying (0.02 mm Hg), 6.7 g (74%) of product was obtained (red orange solid mp 48-50 ° C.).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 2.56 (2H, t, J = 6.4 Hz), 2.73 (2H, t, J = 6.2 Hz), 3.90 (2H, d, J = 5.9 Hz), 5.05 (2H, s), 5.08 (2H, s), 7.36 (10H, s), 7.54 (1H, t, J = 5.7 Hz) .
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 27.2, 33.7, 49.6, 65.42, 65.44, 101.1, 127.6, 127.7, 127.8, 127.9, 128.27, 128.33, 136.1, 137.0, 156.3, 172.0, 174.8, 205.5.

Preparation of 3c-carboxydifluoromethyl 5-amino-4-oxopentanoate hydrochloride This compound was prepared as described in Example 2c with the product of 3b (4.0 g; 8.9 mmol), 10% Produced from palladium on carbon (0.20 g), hydrogen gas, and 2M HCl in diethyl ether (10 mL; 20 mmol) in 2-propanol (75 mL) and tetrahydrofuran (25 mL). After filtration through Celite®, the solution was refiltered through fluted filter paper. After evaporation, a pale amber oil was obtained, which was triturated with diethyl ether (4 × 10 mL) to give 1.6 g (80%) of product (light tan gum solid) . The resulting product is mainly carboxydifluoromethyl 5-amino-4-oxopentanoate hydrochloride, some isopropyl 5-amino-4-oxopentanoate hydrochloride, and some 1- (isopropylcarboxy) It was a mixture containing difluoromethyl 5-amino-4-oxopentanoate hydrochloride. Carboxydifluoromethyl 5-amino-4-oxopentanoate hydrochloride can be isolated from the mixture by standard methods such as preparative HPLC.

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 2.63 (2H, t, J = 6.3 Hz), 2.83 (2H, t, J = 6.5 Hz), 3.96 (2H, br s), 8.37 (3H, br, s).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 27.3, 34.2, 46.5, 171.4, 171.8, 202.5.

Example 4-2 Preparation of carboxyethyl 5-amino-4-oxopentanoate hydrobromide

Preparation of 4a-2- (t-butoxycarbonyl) ethyl 5- (Boc-amino) -4-oxopentanoate N, N′-dicyclohexylcarbodiimide (DCC, 3) at ambient temperature using a syringe under argon. .34 g; 16.2 mmol) was added to 5- (Boc-amino) -4-oxopentanoic acid (3.70 g; 16.0 mmol), t-butyl 3-hydroxypropanoate (dichloromethane (40 mL)). 2.31 g; 15.8 mmol), and to a stirred mixture of 4-dimethylaminopyridine (DMAP, 50 mg) in dry dichloromethane (20 mL). A moderate exothermic reaction was suppressed with an ice-water bath. After stirring at ambient temperature for 2 days, the mixture was filtered with suction through a glass-sintered filter. The residue was washed with dichloromethane (3 × 20 mL). The combined filtrate was evaporated and the residue was purified by 45 × 55 mm silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 1) (500 mL) and 7 × 50 ml fractions were collected. After evaporation of fractions 2-4, 5.45 g (96%) of product was obtained (pale yellow oil).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 1.38 (9H, s), 1.41 (9H, s), 2.49 (2H, t, J = 6.6 Hz), 2.53 (2H, t, J = 6.2 Hz), 2.66 (2H, t, J = 6.4 Hz), 3.76 (2H, d, J = 5.9 Hz), 4.16 (2H, t, J = 6.2 Hz), 7.06 (1H, t, J = 5.8 Hz).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 27.1, 27.6, 28.1, 33.5, 34.3, 49.4, 59.9, 78.0, 80.1, 155.7, 169.6, 171.9, 205.8.

Preparation of 4b-2-carboxyethyl 5-amino-4-oxopentanoate hydrobromide This compound was obtained in 4a product (5.43 g; 15.1 mmol) and acetic acid (15 mL) according to Example 1c. Prepared from 30% HBr. 3.38 g (79%) of product was obtained (amber rubber that did not solidify).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 2.55 (4H, t, J = 6.4 Hz), 2.80 (2H, t, J = 6.3 Hz), 4.00 (2H, d, J = 3.5 Hz), 4.19 (2H, t, J = 6.3 Hz), 8.10 (3H, brs).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 26.9, 33.2, 34.1, 46.6, 60.1, 171.8 (2C), 202.6.

Example 5-Preparation of 3-carboxypropyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 5a-3- (benzyloxycarbonyl) propyl 5- (Boc-amino) -4-oxopentanoate This compound was prepared from benzyl 4-bromobutanoate (7.2 g; described in Example 1a; 28.0 mmol), 5- (Boc-amino) -4-oxopentanoate (6.7 g; 29.0 mmol), triethylamine (2.95 mmol), and ethyl acetate (100 mL). The crude product was purified by 60 × 55 mm silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 2) (750 mL) and 6 × 100 mL fractions were collected. After evaporating fractions 3 and 4, 5.43 g (46%) of product was obtained (yellow oil).

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 1.38 (9H, s), 1.85 (2H, m), 2.41-2.50 (4H, m), 2.67 (2H) , T, J = 6.7 Hz), 3.77 (2H, d, J = 5.8 Hz), 4.02 (2H, t, J = 6.4 Hz), 5.10 (2H, s), 7 .07 (1H, t, J = 5.7 Hz), 7.37 (5H, s).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 23.6, 27.2, 28.1, 30.0, 33.6, 49.4, 63.0, 65.4, 78.0, 127.87, 127.93, 128.4, 136.1, 155.7, 172.1, 172.2, 206.0.

Preparation of 5b-3-carboxypropyl 5- (Boc-amino) -4-oxopentanoate This compound is the product from 5a (5.40 g; 13.2 mmol), described in Example 2c, 10 Prepared from% palladium on activated carbon (250 mg), hydrogen gas, and 96% ethanol (100 mL). 4.30 g of product was obtained (yellowish oil) which was used in 5c without further processing.

Preparation of 5c-3-carboxypropyl 5-amino-4-oxopentanoate hydrochloride This compound is the product of 5b (4.20 g; 13.2 mmol), diethyl ether (7 Prepared from 2M HCl in 5 mL; 15 mmol), and diethyl ether (50 mL). After evaporation of the solvent, the oily residue was triturated with diethyl ether (4 × 10 mL) and kept in the freezer overnight until solidified to a light tan solid. After drying at 12 mm Hg and ambient temperature, 1.90 g (57%) of product was obtained.

¹ H NMR: (300 MHz; DMSO-d ₆ ): δ 1.80 (2H, m), 2.30 (2H, t, J = 7.4 Hz), 2.55 (2H, t, J = 6. 7 Hz), 2.82 (2H, t, J = 6.4 Hz), 3.95 (2H, d, J = 5.1 Hz), 4.03 (2H, t, J = 6.5 Hz), 8. 42 (3H, br s), 12.1 (1 H, br s).
¹³ C NMR: (75 MHz; DMSO-d ₆ ): δ 23.6, 27.0, 30.1, 34.2, 46.4, 63.3, 171.9, 173.8, 202.6.

Example 6-Preparation of carboxyphenylmethyl 5-amino-4-oxopentanoate hydrobromide

Preparation of 6a-t-butyl α-bromophenyl acetate Concentrated sulfuric acid (0.55 mL; 10 mmol) was added to a stirred suspension of anhydrous MgSO ₄ (4.8 g; 40 mmol) in dry dichloromethane (40 mL) at ambient temperature. Added. After stirring for 15 minutes, α-bromophenylacetic acid (2.15 g; 10.0 mmol) was added followed by t-butyl alcohol (4.8 mL; 50 mmol). The reaction flask was closed with a stopper and the mixture was stirred at ambient temperature for 7 days. Saturated NaHCO ₃ solution (75 mL) and water (75 mL) were added to the reaction mixture. After separation, the aqueous layer was extracted with dichloromethane (2 × 15 mL). The combined organic layer was washed with water and dried (MgSO ₄ ). After filtration and evaporation, 2.39 g (88%) of product was obtained (colorless oil).

¹ H NMR: (200 MHz; CDCl ₃ ): δ 1.46 (9H, s), 5.25 (1H, s), 7.30-7.38 (3H, m), 7.48-7.56. (2H, m).
¹³ C NMR: (50 MHz; CDCl ₃ ): δ 27.7, 48.3, 83.0, 128.5, 128.6, 128.9, 136.2, 167.0.

Preparation of 6b-t-butyl α- [5- (Boc-amino) -4-oxopentanoyloxy] -phenylacetate This compound was prepared from 5- (Boc-amino) -4-oxopentanoic acid (1.97 g; 8.5 mmol), the product of 6a (2.35 g; 8.7 mmol), and triethylamine (0.88 g; 8.7 mmol) in ethyl acetate (30 mL) as described in Example 1a. The crude product was purified by 65 × 55 mm silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 2) (1100 mL) and 18 × 50 mL fractions were collected. After evaporating fractions 3-8, 2.79 g (78%) of product was obtained (amber oil).

¹ H NMR: (200 MHz; CDCl ₃ ): δ 1.39 (9H, s), 1.44 (9H, s), 2.75-2.85 (4H, m), 4.05 (2H, d , J = 4.8 Hz), 5.22 (1H, br s), 5.77 (1H, s), 7.35-7.46 (5H, m).
¹³ C NMR: (50 MHz; CDCl ₃ ): δ 27.7, 27.8, 28.3, 34.2, 50.3, 75.2, 79.8, 82.5, 127.4, 128. 8, 128.9, 134.0, 155.7, 167.5, 171.6, 203.7.

Preparation of 6c-carboxyphenylmethyl 5-amino-4-oxopentanoate hydrobromide This compound contains the product of 6b (2.75 g; 6.5 mmol) and acetic acid (5 mL) described in Example 1c. ) Was prepared from 33% HBr. The crude product was purified by 40 × 55 mm silica gel 60 column flash chromatography eluting with 10% methanol in acetonitrile (400 mL) and 20 × 10 ml fractions were collected. Fractions 4-15 were evaporated at 40 ° C. and 0.01 mm Hg for 48 hours and dried under reduced pressure to give 1.60 g (71%) of product (orange foam, mp 77-80 ° C.) .

¹ H NMR: (200 MHz; DMSO-d ₆ ): δ 2.73 (2H, m), 2.85 (2H, m), 4.02 (2H, s), 5.82 (1H, s), 7.3-7.5 (5H, m), 8.13 (3H, br s).
¹³ C NMR: (50 MHz; DMSO-d ₆ ): δ 26.8, 34.1, 46.5, 74.1, 127.4, 127.9, 128.5, 134.0, 169.4, 171.2, 202.1.

Example 7-Preparation of (4-carboxyphenyl) methyl 5-amino-4-oxopentanoate hydrobromide

Preparation of 7a-t-butyl 4- (bromomethyl) benzoate This compound contains 4- (bromomethyl) benzoic acid (2.15 g; 10.0 mmol), t-butyl alcohol (4.8 mL; 50 mmol), anhydrous MgSO 4 ₄ (4.8 g; 40 mmol), and concentrated sulfuric acid (40 mL) in dichloromethane as described in Example 6a. After 14 days, the mixture was processed as described in Example 6a. 1.07 g (39%) of product was obtained (white solid). The product was used for 7b without further purification.

¹ H NMR: (200 MHz; CDCl ₃ ): δ 1.59 (9H, s), 4.49 (2H, s), 7.42 (2H, d, J = 8.4 Hz), 7.96 (2H , D, J = 8.4 Hz).
¹³ C NMR: (50 MHz; CDCl ₃ ): δ 28.1, 32.3, 81.2, 128.7, 129.8, 130.6, 141.9, 165.0.

Preparation of 7b-t-butyl [4- [5- (Boc-amino) -4-oxopentanoyloxy] methyl] -benzoate This compound was prepared from 5- (Boc-amino) -4-oxopentanoic acid ( 0.81 g; 3.50 mmol), the crude product of 7a (1.00 g; 3.7 mmol), and triethylamine (0.40 g; 4.0 mmol) in ethyl acetate (15 mL) described in Example 1a. Prepared. The crude product was purified by 65 × 55 mm silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 2) (1200 mL) and 16 × 50 mL fractions were collected. After evaporating fractions 6-10, 0.59 g (40%) of product was obtained (colorless oil).

¹ H NMR: (200 MHz; CDCl ₃ ): δ 1.44 (9H, s), 1.59 (9H, s), 2.73 (4H, s), 4.05 (2H, d, J = 5) .0Hz), 4.1 (1H, br s), 5.15 (2H, s), 7.37 (2H, d, J = 8.4 Hz), 7.98 (2H, d, J = 8. 2 Hz).
¹³ C NMR: (50 MHz; CDCl ₃ ): δ 27.7, 28.2, 28.3, 34.3, 50.3, 81.1 (2C), 127.4 (2C), 129.6 ( 2C), 131.8, 140.0, 165.2, 172.0, 203.9.

Preparation of 7c- (4-carboxyphenyl) methyl 5-amino-4-oxopentanoate hydrobromide This compound is described in the product of 7b (0.50 g; 1.2 mmol) and in Example 1c. Prepared from 33% HBr in acetic acid (2 mL). The addition of HBr resulted in the immediate precipitation of a white solid. The precipitate was triturated with hexane and diethyl ether as described in Example 1c. The residue was dried under reduced pressure at 40 ° C. and 0.01 mm Hg for 48 hours. 0.37 g (88%) of product was obtained (white powder, mp 198-200 ° C. (dec.)).

¹ H NMR: (200 MHz; DMSO-d ₆ ): δ 2.68 (2H, t, J = 6.2 Hz), 2.88 (2H, t, J = 6.2 Hz), 4.03 (2H, s), 5.19 (2H, s), 7.49 (2H, d, J = 8.0 Hz), 7.96 (2H, d, J = 8.4 Hz), 8.13 (3H, br s) ).
¹³ C NMR: (50 MHz; DMSO-d ₆ ): δ 27.0, 34.2, 46.6, 64.8, 127.3, 129.2, 130.1, 140.8, 166.8, 171.6, 202.4.

Examples 8-15- Preparation of linear carboxyalkyl 5-amino-4-oxopentanoate hydrochloride The linear carboxyalkyl 5-amino-4-oxopentanoate hydrochloride described in Examples 8-15 General structure of salt:

n = 4, 5, 7, 8, 9, 10, 11, 15
General procedure used for the preparation of the compounds of Examples 8-15:
Procedure A Preparation of benzyl ester using carbodiimide A solution of N, N′-diisopropylcarbodiimide in N, N′-dicyclohexylcarbodiimide (DCC) or dry dichloromethane (10 mL) via a syringe under a carboxylic acid , Benzyl alcohol, or 2,2,2-trichloroethanol, and added dropwise to a stirred solution of 4-pyrrolidinylpyridine in dry dichloromethane (40 mL). After stirring for 1 or 2 days at ambient temperature, the mixture was filtered under reduced pressure and the residue was washed with a small amount of dichloromethane. The solvent was evaporated and the residue was dried under reduced pressure at 50 ° C. (bath temperature) and 0.014 mm Hg using a Kugelrohr apparatus to remove excess benzyl alcohol.

Procedure B Preparation of benzyl ester using azeotropic distillation A mixture of carboxylic acid, benzyl alcohol, and p-toluenesulfonic acid in toluene was refluxed overnight through a Dean-Stark trap. After cooling to ambient temperature, the mixture was washed with saturated NaHCO ₃ solution (1 × 15 mL) and saturated NaCl (1 × 15 mL). After drying (MgSO ₄ ), filtration, and evaporation, the residue was dried under reduced pressure at 50 ° C. (bath temperature) and 0.014 mm Hg using a Kugelrohr apparatus.

Procedure C Coupling of esters to N-protected 5-ALA derivatives: ω-bromoalkanoate and cesium 5- (Cbz-amino) -4-oxopentanoate benzyl ω-bromoalkanoate, cesium 5- (Cbz- Amino) -4-oxopentanoate and NaI (10 mg) in dry DMSO (25 mL) were heated to 100 ° C. (bath temperature) overnight under argon. The mixture was cooled to ambient temperature, diluted with water (150 mL) and extracted with diethyl ether (5 × 25 mL). The combined ether solution was washed with water (2 × 10 mL), saturated NaCl solution (1 × 10 mL) and dried (MgSO ₄ ). After filtration and evaporation, the residue was purified by silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 1). Product containing fractions were evaporated to isolate the protected 5-ALA ester.

Procedure D Coupling of esters to N-protected 5-ALA derivatives: N, N ′ in dry dichloromethane (10 mL) under ω-hydroxyalkanoate and 5- (Cbz-amino) -4-oxopentanoic acid argon. -A solution of dicyclohexylcarbodiimide (DCC) was stirred in omega-hydroxyalkanoate, 5- (Cbz-amino) -4-oxopentanoic acid, and 4-pyrrolidinylpyridine (50 mg) in dry dichloromethane (25 mL). Added to. The mixture was stirred at ambient temperature for 1-3 days and then filtered under reduced pressure. The filtrate was evaporated and the residue was purified by silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 1). Product containing fractions were evaporated to isolate the protected 5-ALA ester.

Procedure E Coupling of ester to N-protected 5-ALA derivative: Trichloroethyl ω-hydroxyalkanoate and 5- (Boc-amino) -4-oxopentanoic acid N, in dry dichloromethane (15 mL) under argon. A solution of N′-dicyclohexylcarbodiimide (DCC, 2.41 g; 14.1 mmol) was added to 2,2,2-trichloroethyl ω-hydroxyalkanoate, 5- (Boc-amino) -4-oxopentanoic acid, and 0. Add dropwise to a stirred solution of pyridine in dry dichloromethane cooled to 0 ° C. (bath temperature). After stirring for 1 hour at 0 ° C., the mixture was stirred overnight at ambient temperature. The reaction mixture was filtered under reduced pressure and acetic acid (3 mL) was added to the filtrate. After standing for 30 minutes, the mixture was refiltered and the filtrate was diluted with diethyl ether (150 mL). The solution was washed with 1M HCl (3 × 25 mL), water (3 × 25 mL), saturated NaHCO ₃ solution (2 × 25 mL), and saturated NaCl solution (1 × 25 mL). Dried (MgSO _4), filtered, evaporated and the residue, ethyl acetate - was purified by silica gel 60 column flash chromatography eluting with hexane. Product containing fractions were evaporated to give the product.

Example 8-Preparation of 4-carboxybutyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 8a-benzyl 5-bromopentanoate This compound was prepared using Procedure B using 5-bromopentanoic acid (1.81 g; 10.0 mmol), benzyl alcohol (1.62 g; 15.0 mmol), and toluene. Prepared from p-toluenesulfonic acid (50 mg) in (100 mL). 2.60 g (96%) of product was obtained (clear oil). The product was used for 8c without further purification.

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.8-1.9 (4H, m, J = 7.2 Hz), 2.39 (2H, t, J = 7.2 Hz); 3.39 (2H , T, J = 6.4 Hz); 5.12 (2H, s), 7.35 (5H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 23.5, 31.9, 32.9, 33.2, 66.2, 128.1, 128.2, 128.4, 135.8, 172.7 ppm.

Preparation of 8b-cesium 5- (Cbz-amino) -4-oxopentanoate 5- (Cbz-amino) -4-oxopentanoic acid (2.66 g; 10.0 mmol) in deionized water (40 mL) Of cesium carbonate (1.64 g; 5.0 mmol) was added to the nucleic acid solution. After the evolution of CO ₂ ceased, the mixture was frozen with liquid nitrogen and lyophilized overnight. 4.2 g (about 100%) of product was obtained (light tan solid). The product was used for 8c without further purification.

Preparation of 8c-4- (benzyloxycarbonyl) butyl 5- (Cbz-amino) -4-oxopentanoate This compound was prepared according to Procedure C from the product of 8a (0.73 g; 2.7 mmol) and 8b Prepared from product (1.0 g; 2.5 mmol). The crude product was purified on a 75 × 45 mm silica gel 60 column eluted with ethyl acetate-hexane (1: 1) (1000 mL) and 13 × 50 mL fractions were collected. After collecting fractions containing product (5-8) and evaporation, 0.82 g (72%) of product was obtained (yellowish solid, mp 53-56 ° C.).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.58 (4H, br s), 2.3-2.5 (4H, overlapping t), 2.69 (2H, t, J = 6 Hz) 3.89 (2H, d, J = 5.8 Hz), 3.99 (2H, br s); 5.04 (2H, s), 5.09 (2H, s), 7.36 (10H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 20.9, 23.6, 27.2, 32.8, 33.6, 49.6, 63.4, 65.2, 65.3, 127 .5, 127.6, 127.7, 127.8, 128.1, 128.2, 136.0, 136.8, 156.2, 171.9, 172.3, 205.3 ppm.

Preparation of 8d-4-carboxybutyl 5-amino-4-oxopentanoate hydrochloride Product of 8c (0.70 g; 1.54 mmol), 12 M HCl (0.13 mL; 1.54 mmol), 10% A stirred mixture of Pd / C (Degussa type 101 NE / W) (100 mg) and 2-propanol (25 mL) was hydrogenated overnight at ambient temperature and a pressure of 4 bar. The mixture was filtered through a Celite® 545 pad. The filtrate was evaporated and the residue was triturated with dry diethyl ether (3 × 5 mL). After drying the residue at ambient temperature and 0.01 mm Hg, 0.38 g (97%) of product was obtained (white solid).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.4-1.7 (4H, m), 2.25 (2H, t, J = 6.4 Hz), 2.55 (2H, t, J = 6.4 Hz), 2.82 (2H, t, J = 6.4 Hz), 3.9-4.1 (4H, m), 8.43 (3H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 20.9, 23.5, 27.0, 30.0, 34.2, 46.4, 63.6, 171.8, 173.6, 202 .3 ppm.

Example 9-Preparation of 5-carboxypentyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 9a-benzyl 6-bromohexanoate This compound was prepared using Procedure B using 6-bromohexanoic acid (1.95 g; 10.0 mmol), benzyl alcohol (1.62 g; 15.0 mmol), and toluene. Prepared from p-toluenesulfonic acid (50 mg) in (100 mL). 2.80 g (98%) of product was obtained (clear oil). The product was used for 9b without further purification.
¹ H NMR (200 MHz; CDCl ₃ ): δ 1.4-1.5 (2H, m, J = 6.8 Hz), 1.6-1.7 (2H, m, J = 7.2 Hz), 1 .8-1.9 (2H, m, J = 7.4 Hz), 2.37 (2H, t, J = 7.4 Hz); 3.38 (2H, t, J = 6.6 Hz); 12 (2H, s), 7.35 (5H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.0, 27.7, 32.3, 33.4, 34.0, 66.1, 128.1, 128.4, 135.9, 173.0 ppm.

Preparation of 9b-5- (benzyloxycarbonyl) pentyl 5- (Cbz-amino) -4-oxopentanoate This compound was prepared according to Procedure C from the product of 9a (0.77 g; 2.7 mmol) and 8b Prepared from product (1.0 g; 2.5 mmol). The reaction time was 2 days. The crude product was purified on a 75 × 45 mm silica gel 60 column eluted with ethyl acetate-hexane (1: 1) (1000 mL) and 14 × 50 mL fractions were collected. After collecting and evaporating fractions containing product (5-7), 0.52 g (44%) of product was obtained (amber colored solidified to a waxy solid upon standing in freezer). Oil).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.25-1.38 (2H, m), 1.45-1.6 (4H, m), 2.36 (2H, t, J = 7) .2 Hz), 2.47 (2H, t, J = 6.4 Hz), 2.69 (2H, t, J = 6.2 Hz), 3.85-4.1 (4H, overlapping d and t, J = 6 and 6.4 Hz), 5.04 (2H, s), 5.09 (2H, s), 7.36 (10H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.0, 24.7, 27.2, 27.6, 33.2, 33.6, 49.6, 63.6, 65.2, 65 .3, 127.5, 127.6, 127.7, 127.8, 128.1, 128.2, 136.1, 136.8, 156.2, 171.9, 172.4, 205.3 ppm.

Preparation of 9c-5-carboxypentyl 5-amino-4-oxopentanoate hydrochloride This compound was prepared from the product of 9b (0.45 g; 0.96 mmol), 12 M HCl using the procedure of Example 8d. (0.08 mL; 0.96 mmol) Prepared from 10% Pd / C (100 mg), hydrogen gas, and 2-propanol (25 mL). 0.20 g (77%) of product was obtained (white solid).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.2-1.4 (2H, m), 1.4-1.7 (4H, m), 2.22 (2H, t, J = 7) .2 Hz), 2.55 (2H, t, J = 6.4 Hz), 2.82 (2H, t, J = 6.2 Hz), 3.9-4.1 (4H, m), 8.41 (3H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.0, 24.8, 27.0, 27.7, 33.4, 34.2, 46.4, 63.8, 171.8, 174 .1, 202.3 ppm.

Example 10 Preparation of 7-carboxyheptyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 10a-benzyl 8-bromooctanoate This compound was prepared using Procedure A using 8-bromooctanoic acid (2.23 g; 10.0 mmol), benzyl alcohol (1.19 g; 11.0 mmol), N, Prepared from N′-dicyclohexylcarbodiimide (DCC, 2.27 g; 11.0 mmol) and 4-pyrrolidinylpyridine (50 mg) in dry dichloromethane (50 mL). 3.14 g (100%) of product was obtained (clear oil that finally solidified on standing).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.33 (6H, br s), 1.6-1.7 (2H, m), 1.75-1.9 (2H, m), 2.35 (2H, t, J = 7.8 Hz); 3.38 (2H, t, J = 6.8 Hz); 5.11 (s, 2H), 7.35 (s, 5H) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.8, 27.9, 28.3, 28.9, 32.6, 33.8, 34.2, 66.0, 128.1, 128.4 136.0, 173.3 ppm.

Preparation of 10b-7- (benzyloxycarbonyl) heptyl 5- (Cbz-amino) -4-oxopentanoate This compound was prepared according to Procedure C from the product of 10a (0.79 g; 2.5 mmol) and 8b Prepared from product (1.0 g; 2.5 mmol). The reaction time was 2 days. The crude product was purified by 80 × 45 mm silica gel 60 column eluted with ethyl acetate-hexane (1: 1) (1000 mL) and 13 × 50 mL fractions were collected. After collecting and evaporating fractions containing product (3-6), 0.83 g (67%) product was obtained (amber oil solidified to a waxy solid upon standing in freezer) Product, mp 52-54 ° C.).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.26 (6H, br s), 1.53 (4H, br s), 2.34 (2H, t, J = 7.2 Hz), 2. 48 (2H, t, J = 5.8 Hz), 2.69 (2H, t, J = 6.4 Hz), 3.38 (1H, t, J = 6.6 Hz), 3.89 (2H, d , J = 6 Hz), 3.98 (2H, t, J = 6.6 Hz), 5.04 (2H, s), 5.08 (2H, s), 7.35 (10H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.3, 25.1, 26.3, 27.2, 27.9, 33.4, 33.7, 49.6, 63.8, 65 .1, 65.3, 127.4, 127.7, 128.2, 136.1, 136.8, 156.1, 171.8, 172.5, 205.2 ppm.

Preparation of 10c-7-carboxyheptyl 5-amino-4-oxopentanoate hydrochloride This compound was prepared from the product of 10b (0.70 g; 1.4 mmol), 12 M HCl using the procedure of Example 8d. (0.12 mL; 1.4 mmol) Prepared from 10% Pd / C (100 mg), hydrogen gas, and 2-propanol (25 mL). 0.30 g (70%) of product was obtained (white solid).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.28 (6H, s), 1.4-1.7 (4H, m), 2.20 (2H, t, J = 7 Hz); 55 (2H, t, J = 6.2 Hz), 2.81 (2H, t, J = 6.2 Hz), 3.9-4.1 (4H, m), 8.42 (3H, s) ppm .
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.3, 25.1, 27.0, 27.9, 28.2, 28.3, 33.6, 34.2, 46.4, 63 .9, 171.8, 174.2, 202.3 ppm.

Example 11 Preparation of 8-Carboxyoctyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 11a-benzyl hydrogen nonanedioate Nonane diacid (18.8 g; 0.10 mol), benzyl alcohol (10.8 g; 0.10 mol), and p-toluenesulfonic acid (0.2 g) in toluene (200 mL). The stirred mixture was refluxed overnight through a Dean-Stark trap. The mixture was cooled to ambient temperature and extracted with 10% aqueous N-methyl-D-glucamine (4 × 25 mL). The final extract was a milky white emulsion. The first three extracts were combined, acidified with 1M HCl (50 mL) and filtered to give recovered nonanedioic acid (3.8 g). The emulsion was acidified with 1M HCl and allowed to separate overnight. The organic layer was evaporated and the residue was dissolved in hexane (200 mL) and diethyl ether (50 mL). The solution was extracted with 10% N-methyl-D-glucamine (2 × 50 mL) (emulsion destroyed by adding a small amount of ethanol). The organic solution was washed with water (1 × 25 mL) and the aqueous mixture was acidified with 1M HCl (150 mL). After extraction with dichloromethane-tetrahydrofuran (4: 1) (5 × 10 mL), the combined extracts were dried (Na ₂ SO ₄ ), filtered and evaporated. 13.0 g (47%) of product was obtained (oil solidified on standing).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.31 (6H, br s), 1.5-1.8 (4H, m), 2.25-2.4 (4H, m); 5.11 (S, 2H), 7.34 (5H, s), 10.4 (1H, br s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.6, 28.8, 34.0, 34.2, 66.1, 128.1, 128.4, 136.0, 173.5, 179.9 ppm.

Preparation of 11b-benzyl 9-hydroxynonanoate The product of 11a (12.9 g; 46.3 mmol) was added to a stirred mixture of sodium borohydride (1.70 g; 45.0 mmol) in dry tetrahydrofuran (25 mL). Added in increments. After hydrogen evolution ceased, a solution of boron trifluoride dimethyl ether compound (4.6 mL; 5.7 g; 50 mmol) in dry tetrahydrofuran (15 mL) was added dropwise. The exothermic reaction was suppressed with a cold water bath. After stirring at ambient temperature for 4 hours, the reaction mixture was hydrolyzed with cold water (20 mL). The mixture was separated and the organic phase was evaporated. The residue was mixed with water (20 mL) and dichloromethane (70 mL) and left overnight to give a separated emulsion. The organic phase was washed with water (4 × 15 mL) until the wash was neutral to pH paper. After drying (Na ₂ SO ₄ ), filtered and evaporated, 11.95 g (98%) of product was obtained (oil).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.30 (8H, br s), 1.4-1.75 (4H, m), 2.34 (2H, t, J = 7.6); 3 .62 (2H, t, J = 6.6 Hz), 5.10 (2H, s), 7.34 (5H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.9, 25.6, 29.0, 29.1, 32.6, 34.3, 63.0, 66.0, 128.0, 128.4 136.0, 173.6 ppm.

Preparation of 11c-8- (benzyloxycarbonyl) octyl 5- (Cbz-amino) -4-oxopentanoate This compound was prepared according to Procedure D from the product of 11b (1.1 g; 4.2 mmol), 5- (Cbz-amino) -4-oxopentanoic acid (1.0 g; 3.8 mmol), 4-pyrrolidinylpyridine (60 mg), and N, N′-dicyclohexylcarbodiimide (DCC, 0.001) in dichloromethane (35 mL). 87 g; 4.2 mmol). The reaction time was 3 days. The crude product was purified by 85 × 45 mm silica gel 60 column eluted with ethyl acetate-hexane (1: 1) (1000 mL) and 14 × 50 mL fractions were collected. Fractions containing product (4-7) were evaporated to give 1.5 g (77%) of product.

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.24 (8H, br s), 1.54 (4H, overlapping t, J = 6.2 Hz), 2.34 (2H, t, J = 7.2 Hz), 2.48 (2H, t, J = 6.2 Hz), 2.69 (2H, t, J = 6.2 Hz), 3.89 (2H, d, J = 6 Hz), 3. 97 (2H, t, J = 6.6 Hz), 5.04 (2H, s), 5.08 (2H, s), 7.35 (10H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 23.6, 24.3, 25.0, 27.2, 27.9, 33.3, 33.6, 49.6, 63.8, 65 .1, 65.3, 127.5, 127.6, 127.7, 128.1, 128.2, 136.1, 136.8, 156.2, 171.9, 172.5, 205.3 ppm.

Preparation of 11d-8-carboxyoctyl 5-amino-4-oxopentanoate hydrochloride This compound was prepared from the product of 11c (1.4 g; 2.7 mmol), 12 M HCl using the procedure of Example 8d. (0.25 mL; 3.0 mmol) Prepared from 10% Pd / C (100 mg), hydrogen gas, and 2-propanol (25 mL). 0.54 g (62%) of product was obtained (white solid).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.1-1.7 (12H, m), 2.20 (2H, t, J = 7.4 Hz), 2.54 (2H, t, J = 6.4 Hz), 2.81 (2H, t, J = 6.4 Hz), 3.9-4.1 (4H, m), 8.40 (3H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.4, 25.1, 27.0, 28.0, 28.4, 28.5, 33.5, 34.2, 46.4, 63 .9, 171.8, 174.2, 202.3 ppm.

Example 12-Preparation of 9-carboxynonyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 12a-2,2,2-trichloroethyl 10-hydroxydecanoate A solution of N, N′-dicyclohexylcarbodiimide (DCC, 2.41 g; 14.1 mmol) in dry dichloromethane (15 mL) under argon. In dry dichloromethane (35 mL) cooled to 10-hydroxydecanoic acid (1.88 g; 10.0 mmol), 2,2,2-trichloroethanol (6.13 g; 41.0 mmol) and 0 ° C. (bath temperature) Of pyridine (4.1 mL) was added dropwise. After stirring for 1 hour at 0 ° C., the mixture was stirred overnight at ambient temperature. The reaction mixture was filtered under reduced pressure and acetic acid (3 mL) was added to the filtrate. After standing for 30 minutes, the mixture was refiltered and the filtrate was diluted with diethyl ether (150 mL). The solution was washed with 1M HCl (3 × 25 mL), water (3 × 25 mL), saturated NaHCO ₃ solution (2 × 25 mL), and saturated NaCl solution (1 × 25 mL). After drying (MgSO ₄ ), filtering and evaporation, the residue was purified by 170 × 25 mm silica gel 60 column flash chromatography eluting with ethyl acetate-hexane (1: 1) to give a 12 × 25 mL fraction. Collected. In order to evaporate fractions 3-5 and remove excess 2,2,2-trichloroethanol, the residue was dried under vacuum at 50 ° C. and 0.05 mm Hg in a Kugelrohr apparatus. 2.1 g (66%) of product was obtained (colorless oil).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.32 (10H, br s), 1.4-1.8 (5H, m), 2.47 (2H, t, J = 7.2 Hz); 3 .63 (2H, t, J = 6.4 Hz), 4.74 (2H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.7, 25.6, 29.0, 29.1, 29.28, 29.32, 32.6, 33.9, 63.0, 73.8 95.0, 172.1 ppm.

Preparation of 12b-2,2,2-trichloroethyl 10- [5- (Boc-amino) -4-oxopentanoyloxy] decanoate This compound was prepared using procedure E using 5- (Boc-amino) -4 -Oxopentanoic acid (1.00 g; 4.3 mmol), product from 12a (1.37 g; 4.3 mmol), N, N'-dicyclohexylcarbodiimide (DCC, 1.03 g; 5.0 mmol), and dichloromethane Prepared from pyridine (2.0 mL) in (40 mL). The crude product was purified on a 100 × 50 mm silica gel 60 column eluted with ethyl acetate-hexane (1: 2) and 16 × 50 mL fractions were collected. Evaporation of fractions 4-9 gave 1.6 g (71%) of product (yellowish oil).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.31 (10H, br s), 1.44 (9H, s), 1.5-1.8 (4H, m), 2.46 (2H, t , J = 7.2 Hz), 2.6-2.8 (4H, m), 4.0-4.1 (4H, m), 4.74 (2H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.7, 25.7, 25.8, 27.8, 28.3, 28.5, 28.9, 29.2, 29.3, 32.7 33.9, 50.3, 64.9, 73.8, 95.0, 171.9, 172.3, 204 ppm.

12c-9-Karubokishinoniru 5-(Boc-amino) -4-oxo-pentanoate potassium dihydrogen phosphate Preparation 1 mole of benzoate _(KH 2 PO ₄₎ solution (4.0 mL; 4.0 mmol), followed by Zinc powder (2.0 g; 30 mmol) was added to a stirred solution of the product from 12b (1.50 g; 2.8 mmol) in tetrahydrofuran (25 mL). After stirring for 18 hours at ambient temperature, a new small amount of 1M KH ₂ PO ₄ solution (5 mL) and zinc (2.0 g; 30 mmol) were added. After 5 hours, a further 1M KH ₂ PO ₄ solution (25 mL) was added and the mixture was stirred overnight at ambient temperature. The mixture was filtered under reduced pressure and the residue was washed with ethyl acetate. The ethyl acetate in the filtrate was evaporated and the aqueous solution was extracted with dichloromethane (4 × 5 mL). The combined extract was dried (Na ₂ SO ₄ ), filtered and evaporated. 1.04 g (93%) of product was obtained (pale yellow waxy solid).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.30 (10H, br s), 1.44 (9H, s), 1.5-1.7 (4H, m), 2.34 (2H, t , J = 7.4 Hz), 2.6-2.8 (4H, m), 4.0-4.1 (4H, m) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.7, 25.7, 25.8, 27.8, 28.3, 28.5, 29.0, 29.1, 29.2, 29.3 32.6, 34.0, 50.3, 65.0; 172.4, 179.1 ppm.

Preparation of 12d-9-carboxynonyl 5-amino-4-oxopentanoate hydrochloride Under argon, a 1.0 M solution of HCl in diethyl ether at ambient temperature (7.0 mL; 7.0 mmol) was diluted with ethyl acetate. To a stirred solution of the product from 12c (1.0 g; 2.5 mmol) in (10 mL). After 7 hours, excess solvent was evaporated and the residue was triturated with diethyl ether (4 × 5 mL). The residue was dried overnight at 40 ° C. and 15 mm Hg to give 0.11 g of a white solid. The combined ether extracts were evaporated and dissolved in 1M HCl in 96% ethanol (25 mL) and diethyl ether (5 mL). After stirring for 10 days at ambient temperature, the mixture was filtered and the residue was triturated with diethyl ether as before to give 0.22 g of a second crop. LC-MS analysis showed that the product contained about 30% 5-amino-4-oxopentanoic acid and the mixed crop was acetonitrile (100 mL), 2.5% methanol in acetonitrile (500 mL). Purified by 165 × 25 mm silica gel 60 column flash chromatography, eluted sequentially with 5% methanol in acetonitrile (500 mL), then 7% methanol in acetonitrile (1000 mL) to give a 47 × 50 mL fraction. It was. The product containing fractions were evaporated and the residue was dissolved in water (10 mL). The solution was lyophilized overnight to give 0.17 g (20%) of product (white solid, mp 98-102 ° C., softening, no sharp mp).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.26 (10H, br s), 1.4-1.6 (4H, m), 2.19 (2H, t, J = 7.4 Hz) 2.54 (2H, t, J = 6.4), 2.81 (2H, t, J = 6.6 Hz), 3.9-4.1 (4H, m), 8.5 (3H, br s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.4, 25.2, 27.0, 28.0, 28.4, 28.48, 28.54, 28.6, 33.6, 34 .2, 46.4, 63.9, 171.8, 174.1, 202.3 ppm.

Example 13 Preparation of 10-carboxydecyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 13a-benzyl 11-bromoundecanoate This compound was prepared using Procedure B using 11-bromoundecanoic acid (2.65 g; 10.0 mmol), benzyl alcohol (1.62 g; 15.0 mmol), and toluene. Prepared from p-toluenesulfonic acid (50 mg) in (100 mL). 3.62 g of product was obtained, which was used for 13b without further purification.

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.27 (12H, br s), 1.6-1.7 (2H, m), 1.8-1.9 (2H, m), 2.35 (2H, t, J = 7.4 Hz); 3.39 (2H, t, J = 6.8 Hz); 5.11 (2H, s), 7.34 (5H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.9, 28.1, 28.7, 28.8, 29.0, 29.1, 29.3, 32.8, 33.9, 34.3 66.0, 128.0, 128.4, 136.0, 173.4 ppm.

Preparation of 13b-10- (benzyloxycarbonyl) decyl 5- (Cbz-amino) -4-oxopentanoate This compound was prepared according to Procedure C from the product of 3a (0.96 g; 2.7 mmol) and 8b Prepared from product (1.0 g; 2.5 mmol). The crude product was purified by a 70 × 45 mm silica gel 60 column eluted with ethyl acetate-hexane (1: 1) (1000 mL) and 13 × 50 mL fractions were collected. The fraction containing the product (3) was evaporated to give 0.69 g (47%) of product (pinkish solid, mp 70-72 ° C.).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.23 (12H, br s), 1.54 (4H, br s), 2.34 (2H, t, J = 7.2 Hz), 2. 48 (2H, m), 2.69 (2H, t, J = 6.2 Hz), 3.89 (2H, d, J = 6.6 Hz), 3.98 (2H, t, J = 6.2 Hz) ), 5.04 (2H, s), 5.08 (2H, s), 7.35 (10H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 23.6, 24.3, 25.2, 27.2, 28.0, 28.3, 28.5, 28.7, 33.4, 33 .6, 49.6, 63.8, 65.1, 65.3, 127.5, 127.6, 127.7, 128.1, 128.2, 136.1, 136.8, 156.2 171.9, 172.5, 205.3 ppm.

Preparation of 13c-10-carboxydecyl 5-amino-4-oxopentanoate hydrochloride This compound was prepared using the procedure of Example 8d, the product of 13b (0.60 g; 1.1 mmol), 12M HCl ( Prepared from 0.09 mL; 1.1 mmol), 10% Pd / C (100 mg), hydrogen gas, and 2-propanol (25 mL). 0.20 g (51%) of product was obtained (white solid).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.1-1.7 (16H, m), 2.19 (2H, t, J = 7.4 Hz), 2.54 (2H, t, J = 6.4 Hz), 2.81 (2H, t, J = 6.4 Hz), 3.9-4.1 (4H, m), 8.41 (3H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.4, 25.2, 27.0, 28.0, 28.4, 28.55, 28.62, 28.74, 33.6, 34 .2, 46.4, 64.0, 170.6, 171.8, 202.3 ppm.

Example 14-11 Preparation of 1-carboxyundecyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 14a-2,2,2-trichloroethyl 12-hydroxydodecanoate This compound was prepared using the procedure of Example 12a using 12-hydroxydodecanoic acid (2.0 g; 9.2 mmol), 2,2, Prepared from 2-trichloroethanol (6.0 g; 40 mmol), N, N′-dicyclohexylcarbodiimide (DCC, 4.1 g; 20 mmol), and pyridine (5.0 mL) in dry dichloromethane (50 mL). 3.63 g (66%) of product was obtained (colorless oil).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.28 (14H, br s), 1.5-1.75 (4H, m), 2.46 (2H, t, J = 7.6 Hz); 3 .63 (2H, t, J = 6.4 Hz), 4.74 (2H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.7, 25.7, 28.6, 29.0, 29.1, 29.2, 29.4, 32.7, 33.9, 62.9 73.8, 95.0, 172.0 ppm.

Preparation of 14b-2,2,2-trichloroethyl 12- [5- (Boc-amino) -4-oxopentanoyloxy] dodecanoate This compound was prepared using Procedure E using 5- (Boc-amino) -4 -Oxopentanoic acid (2.0 g; 8.6 mmol), 14a product (3.0 g; 8.6 mmol), N, N'-dicyclohexylcarbodiimide (DCC, 2.1 g; 10.0 mmol) and dichloromethane (75 mL) ) In pyridine (4.0 mL). The crude product was purified on a 90 × 50 mm silica gel column eluted with ethyl acetate-hexane (1: 3) and 13 × 50 mL fractions were collected. After evaporating fractions 6-11, 1.44 g (30%) of product was obtained (yellowish oil).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.28 (14H, br s), 1.45 (9H, s), 1.5-1.8 (4H, m), 2.46 (2H, t , J = 7.4 Hz), 2.6-2.8 (4H, m), 4.0-4.1 (4H, m), 4.74 (2H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.7, 25.8, 28.3, 28.5, 29.1, 29.2, 29.3, 29.4, 29.5, 33.9 34.3, 50.3, 64.9, 73.8, 74.1, 95.0, 172.0, 172.3, 204.1 ppm.

Preparation of 14c-11-carboxyundecyl 5- (Boc-amino) -4-oxopentanoate This compound was prepared according to the procedure of Example 12c, using the same amount of 1M KH ₂ PO ₄ solution and zinc powder. Prepared from 14b product (1.38 g; 2.5 mmol) in tetrahydrofuran (25 mL). After treatment, 1.0 g (93%) of product was obtained (pale yellow oil).

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.28 (14H, br s), 1.44 (9H, s), 1.5-1.7 (4H, m), 2.33 (2H, t , J = 7.4 Hz), 2.6-2.8 (4H, m), 4.0-4.1 (4H, m) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.7, 25.8, 28.3, 28.5, 29.0, 29.2, 29.3, 29.4, 32.6, 34.0 50.3, 65.0, 172.4, 178.9, 204.3 ppm.

Preparation of 14d-11-carboxyundecyl 5-amino-4-oxopentanoate hydrochloride Under argon, a 1.0 M solution of HCl in diethyl ether at ambient temperature (5.0 mL; 5.0 mmol) was added to acetic acid. To a stirred solution of the product from 14c (0.95 g; 2.2 mmol) in ethyl (10 mL). After 5 days, the mixture was filtered and the residue was triturated with diethyl ether (2 × 5 mL). The residue was dried overnight at 40 ° C. and 15 mm Hg to give 0.11 g of a white solid. The combined ether extracts were evaporated. LC-MS analysis indicated that the product contained approximately 25% 5-amino-4-oxopentanoic acid, and the mixed crop was 6% in acetonitrile (1000 mL), 6% in acetonitrile (1000 mL). Purified by 150 × 25 mm silica gel 60 column flash chromatography, eluting successively with 9% methanol followed by 9% methanol in acetonitrile (2000 mL), collecting 56 × 50 mL fractions. The product containing fractions were evaporated and the residue was dissolved in water (10 mL). The solution was lyophilized overnight to give 0.06 g (7.5%) of product (white solid, mp 110-115 ° C. (softening, no sharp mp)).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.25 (14H, br s), 1.4-1.6 (4H, m), 2.19 (2H, t, J = 7.4 Hz) 2.55 (2H, t, J = 6.2 Hz), 2.80 (2H, t, J = 6.4 Hz), 3.9-4.1 (4H, m), 9.1 (3H, br s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.4, 25.2, 27.0, 28.0, 28.4, 28.5, 28.6, 28.8, 33.6, 34 .1, 46.4, 64.0, 171.8, 174.2, 202.4 ppm.

Example 15-15 Preparation of 5-carboxypentadecyl 5-amino-4-oxopentanoate hydrochloride

Preparation of 15a-benzyl 16-hydroxyhexadecanoate This compound was prepared using Procedure B using 16-hydroxyhexadecanoic acid (2.45 g; 9.0 mmol), benzyl alcohol (4.9 g; 45 mmol), and toluene ( Prepared from p-toluenesulfonic acid (100 mg) in 100 mL). 2.82 g of crude product was obtained, which was a 1: 1 mixture of the expected product and an ester between two molecules of 16-hydroxyhexadecanoic acid. A solution of NaH (ca. 100 mg) in benzyl alcohol (10 g) (previously washed 3 times with dry hexane) was added to the crude product and the mixture was heated at 100 ° C. (bath temperature) for 3 h under argon. Stir. After cooling to ambient temperature, the mixture was diluted with dichloromethane (75 mL), washed with 10% aqueous citric acid solution (1 × 10 mL) and dried (Na ₂ SO ₄ ). After filtration and evaporation, the residue was dried under reduced pressure at 50 ° C. (bath temperature) and 0.014 mm Hg using a Kugelrohr apparatus. 2.56 g (76%) of product was obtained (white solid). Proton NMR showed that about 10% of the dimer ester remained.

¹ H NMR (200 MHz; CDCl ₃ ): δ 1.25 (22H, br s), 1.55-1.65 (4H, m, J = 7.6 Hz), 1.9 (1H, br s), 2.35 (2H, t, J = 7.4 Hz); 3.63 (2H, t, J = 6.6 Hz); 5.11 (2H, s), 7.34 (5H, s) ppm.
¹³ C NMR (50 MHz; CDCl ₃ ): δ 24.9, 25.7, 28.9, 29.1, 29.2, 29.4, 29.6, 32.8, 34.3, 63.0 66.0, 128.0, 128.2, 128.4, 136.0, 173.6 ppm.

Preparation of 15b-15- (benzyloxycarbonyl) pentadecyl 5- (Cbz-amino) -4-oxopentanoate This compound was prepared according to Procedure D from the product of 15a (1.2 g; 3.2 mmol), 5- N, N′-diisopropylcarbodiimide (0.50 g; in (Cbz-amino) -4-oxopentanoic acid (0.84 g; 3.2 mmol), 4-pyrrolidinylpyridine (50 mg), and dichloromethane (35 mL); 4.0 mmol). The reaction time was 3 days. The crude product was purified by 85 × 55 mm silica gel 60 column eluted with ethyl acetate-hexane (1: 1) (1000 mL) and 13 × 50 mL fractions were collected. Fractions containing product (3-6) were evaporated to give 0.57 g (29%) of product (white solid, mp 78-81 ° C.).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.24 (22H, br s), 1.54 (4H, br s), 2.33 (2H, t, J = 7.4 Hz), 2. 48 (2H, br s), 2.68 (2H, br s), 3.88 (2H, br s), 3.98 (2H, br s), 5.04 (2H, s), 5.08 (2H, s), 7.34 (10H, s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.4, 25.3, 27.4, 28.1, 28.3, 28.6, 28.9, 33.5, 33.8, 49 .8, 63.9, 65.2, 65.5, 127.4, 127.6, 127.7, 128.1, 128.2, 136.9, 171.8, 205.2 ppm.

Preparation of 15c-15-carboxypentadecyl 5-amino-4-oxopentanoate hydrochloride This compound was prepared from the product of 15b (0.45 g; 0.74 mmol), 12 M using the procedure of Example 8d. Prepared from HCl (0.062 mL; 0.74 mmol), 10% Pd / C (100 mg), hydrogen gas, and 2-propanol (25 mL). 0.06 g (19%) of product was obtained (white solid).

¹ H NMR (200 MHz; DMSO-d ₆ ): δ 1.1-1.7 (28H, m), 2.25 (2H, m), 2.52 (2H, m), 2.82 (2H, m), 3.9-4.1 (4H, m), 8.43 (3H, s), 12.1 (1H, br s) ppm.
¹³ C NMR (50 MHz; DMSO-d ₆ ): δ 24.4, 25.3, 27.0, 27.2, 27.6, 28.0, 28.4, 28.6, 28.9, 33 .6, 34.2, 46.4, 63.9, 171.8, 174.1, 202.3 ppm.

Example 16-In vivo skin fluorescence studies in healthy nude mice A study was conducted to evaluate the potential of the compounds of the present invention as precursors of photosensitizers for skin use. Therefore, the compounds of the present invention need to penetrate the skin, be taken up by skin cells and converted to photosensitizers. The result of this process is the exposure of the skin to light that excites the photosensitizer molecule, and the energy released in the form of fluorescence when the excited photosensitizer molecule is relaxed to an energetically lower state. Visualized by determining the amount.

The following compounds of the present invention were tested on the skin of healthy nude mice.
Compound 2: 1- (Isopropylcarboxy) ethyl 5-amino-4-oxopentanoate hydrochloride (prepared according to Example 2)
Compound 4: 2-carboxyethyl 5-amino-4-oxopentanoate hydrobromide (prepared according to Example 4)
Compound 7: (4-Carboxyphenyl) methyl 5-amino-4-oxopentanoate hydrobromide (prepared according to Example 7)
Compounds 2, 4, and 7 above were formulated as creams at Unguentum Merck. Compounds were tested in equimolar amounts.
16% (160 mg / g) of compound 2
16% (160 mg / g) of compound 4 and 19% (190 mg / g) of compound 7.

  Three groups of mice (5 mice / group, each group of mice received the same cream formulation) were included in the experiment. About 100 μl of the cream formulation was applied to the back of one mouse. To avoid photobleaching, mice were kept in the dark for 6 hours prior to skin fluorescence measurements. In order to evaluate skin fluorescence, an image of the back of each mouse was taken using a fluorescence camera (Medeikonos PDD / PDT, Medeikonos AB, Gothenburg, Sweden). Excitation was performed at wavelengths of 365 and 405 nm and an illumination time of 2 seconds. Each image was calibrated to fluorescence standards (Uranyl Standard, J & M, Analytische Mess-und Regeltechnik GmbH, Hamburg, Germany) and adjusted to background fluorescence. The average amount of skin fluorescence in each image was calculated by means of an image analyzer-software (MatLab 72.0.232, Math-Works, Natick, MA, USA), and for each group of mice (5 / compound) The average amount of skin fluorescence was calculated.

  All three compounds tested produced skin fluorescence where 1- (isopropylcarboxy) ethyl 5-amino-4-oxopentanoate hydrochloride of Compound 2 showed the highest fluorescence level.

Example 17-In vivo skin fluorescence study in minipig Compound 1c (carboxymethyl 5-amino-4-oxopentanoate hydrobromide, prepared according to Example 1c) was formulated as a cream in Ungentum Merck (15 %, 150 mg / g; 0.56 mmol).

  The cream was applied to the skin on the back of the minipigs. Prior to applying the cream, the surrounding skin was washed with sterile water and gauze if necessary. 0.5 g of cream was applied to each test site (diameter 50 mm) to provide a homogeneous cream layer and then covered with a dressing (Tegaderm®). A gauze Vet-Flex® was used to hold the dressing in place.

  Skin fluorescence at 630 nm was evaluated before applying the cream and 1.5, 5 and 12 hours after applying the cream using a FluoDerm instrument (DiaMedico ApS, Denmark) according to the manufacturer's instructions. The FluoDerm instrument is a hand-held device for objective real-time in vivo measurements of average fluorescence over a 40 mm diameter circular field. Measurements were electronically corrected for actual ambient light. The results are shown in FIG.

result:
As can be seen in FIG. 1, skin fluorescence increased with time.

Skin biopsy:
The cream was applied as described above. Biopsy samples were taken using a 10 mm biopsy punch (AcuPunch 10 mm, Accuderm, USA) at t = 0 (ie before applying the cream), 1.5, 5, and 12 hours. Samples were collected and handled in a minimally lit room. Each sample was trimmed so as not to contain any subcutaneous adipose tissue and then cut in half. Each sample was then snap frozen in liquid nitrogen in an aluminum foil bag or the like and transferred to a −80 ° C. freezer.

  The biopsy sample was divided into 10 μm, as well as care was taken to minimize ambient light. Where sebaceous glands and epidermis could be identified, a series of three consecutive portions were prepared from each sample. The part was examined within 15 minutes on a Leica DMRXE microscope equipped for both regular light and fluorescence microscopy. The epidermis and sebaceous glands were localized using a conventional light microscope. This was done within 5 seconds and then the light source was switched to a mercury lamp / fluorescence with filter set; excitation filter 390-447 nm, beam splitter 455 nm and emission filter> 600 nm. This part was filmed immediately. Without moving the specimen, the light source was replaced with a conventional optical microscope, and this portion was photographed at the same position as the fluorescence microscope. Similar to the epidermis and sebaceous glands, the dermis was analyzed and if fluorescence was found, it was also photographed. This portion was stained with hematoxylin / eosin to further verify the localization of all structures analyzed.

  Image analysis was performed using a software program of ImageJ (version Fiji-win32.exe). Using this program, the average fluorescence intensity per pixel was measured from the stored images.

result:
After 1.5 hours fluorescence was already visible in the sebaceous glands and after 5 hours fluorescence was also seen in the epidermis. Compound 1c thus exhibits selectivity for sebaceous glands and therefore photodynamics of diseases affecting the sebaceous glands such as acne, pore keratosis, sebum hyperplasia, sebaceous carcinoma, or sebaceous adenoma May be useful for therapeutic treatment.

Example 18-In Vivo Skin Fluorescence Study in Healthy Nude Mice and Nude Mice with UV Damaged Skin Experiments were conducted to evaluate the potential of Compound 6 that shows selective accumulation in UV damaged skin. For evaluation, skin fluorescence was measured in vivo in healthy and UV-damaged mouse skin after compound application. Nude mouse models with UV-damaged skin (sun damage) are Togsverd-Bo et al. , Exp. Dermatol. Established as described in 2012, 21, 260-264.

  Equimolar amounts of Compound 2 (1- (isopropylcarboxy) ethyl 5-amino-4-oxopentanoate hydrochloride prepared according to Example 2) and Compound 5 (3-carboxypropyl 5 prepared according to Example 5) Amino-4-oxopentanoate hydrochloride) was formulated as a cream in Unguentum Merck: Compound 2: 16%, 160 mg / g and Compound 5: 14%, 140 mg / g, respectively.

  One group of healthy nude mice (10 mice, control group) and one group of nude mice with UV-damaged skin (10 mice) were included in the experiment. About 125 μl of the cream formulation was applied to the back of each mouse. Prior to application of the cream, the dorsal skin of each mouse was tape stripped 5 times to improve compound penetration. An adhesive film (Scotch tape, 3M) was pressed against the skin in the application area, the tape strip moved quickly once and a new tape strip was used. To avoid photobleaching, mice were kept in the dark for 3 hours prior to skin fluorescence measurements. Skin fluorescence was evaluated as described in Example 17, and the average amount of skin fluorescence for each group of mice was calculated.

result:
Skin fluorescence of the skin of UV-damaged mice [a. u] skin fluorescence in healthy mouse skin [a. u. ] Ratio was determined.

  The ratio of Compound 2 was 1.14, but the ratio of Compound 5 was 2.72. Thus, compound 2 shows some selectivity for UV-damaged skin, while compound shows significant selectivity for UV-damaged skin.

Example 19-PDT efficacy in bacteria The effectiveness of various compounds according to the present invention to kill bacteria via a photodynamic response was verified in the Gram-positive bacterium Staphylococcus aureus.

The following compounds of the invention were tested.
Compound 1c: Carboxymethyl 5-amino-4-oxopentanoate hydrobromide (prepared according to Example 1c)
Compound 4: 2-carboxyethyl 5-amino-4-oxopentanoate hydrobromide (prepared according to Example 4)
Bacterial strain: S. Aureus strain DSM 20231 (ATCC 12600). Bacterial strains were grown on cardiac exudate agar (Difco) at 35-37 ° C. for 24 hours prior to performing the experiment, at a concentration corresponding to McFarland 0.5 standard (approximately 1-5 × 10 ⁸ CFU / mL) Of 20 mM PIPES, pH 7.2-7.4. To ensure viable cell culture and check inoculum size and purity, bacterial stocks were made immediately prior to the experiment and CFU / mL was determined in a standard colony assay.

Dark Toxicity: “Dark Toxicity”, ie, the toxic effects of compounds in the absence of light (and thus independent of PDT effects) can include bacterial cell death and thus also lead to bacterial cell death. May interfere with accurate measurement of action. Dark toxicity can be measured by determining the toxicity of each compound under the same experimental conditions but in the absence of light, thereby avoiding any PDT effects. The use of the compounds of the invention under conditions that produce low dark toxicity is advantageous because dark toxicity effects can include harming or killing non-target cells and interfering with PDT treatment itself. In view of these considerations, the optimal agent for use in PDT-mediated bacterial cell killing has both low dark toxicity and high potency to induce photodynamic effects to kill target bacterial cells. Should show.
Dark toxicity is determined as described in the “PDT treatment” paragraph below, except that the plate was not illuminated. Subsequently, a microplate assay was performed as described below.

  The dark toxicity of compounds 1c and 4 was tested at concentrations of 0.001, 0.1, 1, and 10 mM. Dark toxicity was not observed at any of these concentrations.

PDT treatment: Compound 1c and 4 stock solutions were made in 100 mM DMSO. Prior to the experiment, 0.02 mL of DMSO (control) or Compound 2 and 3 stock solutions were pipetted into VisiPlates-24 wells to obtain concentrations of 0.01 mM, 0.1 mM, and 1 mM. 2 mL of bacterial stock culture was added to each well and mixed using an automatic pipette. All wells contained DMSO at a final concentration of 1%. After 4 hours of incubation, the plates were illuminated with red light (Aklite ™ CL128 lamp) for 32 minutes (light dose 148 J / cm ² ). In order to achieve uniform illumination to all wells, the plate was illuminated from below (flat bottom well) with a small circular motion in the area where the lamp was applied.

  Microplate assay: After illumination, the entire contents of the wells were transferred to an Eppendorf tube and 0.1 mL of the contents were reintroduced into the wells of the microplate. To generate a growth curve, 1.5 mL of cardiac exudate broth (Difco) was added to the reintroduced inoculum. All transitions proceeded with thorough mixing of the contents by pipetting.

  Plates were incubated at 37 ± 1 ° C. by applying the temperature function of Victor 1420 Multilabel Counter (Perkin Elmer, Turku, Finland). Growth curves were generated by measuring absorbance at 595 nm at regular intervals until the bacterial cells entered the logarithmic growth phase. Measurements were made automatically by a Multilabel Counter.

  The raw data is plotted on the semi-log axis (log 10 absorbance versus time (1 unit = 15 minutes)) to determine the time after inoculation of bacterial cells into logarithmic growth phase (ie, the length of the lag phase). It was done. The length of the lag phase depends on the number of viable cells and increases in proportion to the effectiveness of photodynamic therapy.

result:
The results are shown in FIG. It can be seen from this figure that it is effective in killing Aureus bacteria and can effectively delay bacterial cell regrowth.

Example 20-Ames test Ames test (see B. N. Ames et al, Methods for detecting carcinogens and mutagens with the Salmonella / mammalian-microsmutation test. A standard test method approved by regulatory agencies to detect the ability to induce mutations in a particular bacterial strain. If a test chemical compound induces such a mutation, it cannot be used in a pharmaceutical compound for use in humans.

  The purpose of this study was to identify two histidine-requiring strains of Salmonella typhimurium TA98 and TA100 in the absence and presence of rat liver metabolic system (S-9) and in the absence and presence of visible light. By examining its ability to recover, the mutagenic potential and photomutagenicity of carboxymethyl 5-amino-4-oxopentanoate hydrobromide of compound 1c (prepared according to Example 1c) ( This was to evaluate the possibility of photomutagenic. The latter was evaluated because Compound 1c was taken up by bacterial cells and converted to a photosensitizer that could induce mutagenic products upon illumination of the cells.

  The results indicate that Compound 1c did not induce mutations or photomutation in these two strains of Salmonella typhimurium when tested under the conditions employed in this study.

Example 21-In Vitro PpIX Fluorescence Study in Cancer Cells A study was conducted to evaluate the potential of the compounds of the present invention as precursors of photosensitizers. Therefore, the compounds of the present invention need to be taken up by cells and need to be converted to photosensitizers, ie PpIX. The result of this process is by exposing the cell to light that excites the PpIX molecule and determining the amount of energy released in the form of fluorescence when the excited PpIX molecule is relaxed to an energetically lower state. Visualized.

The following compounds of the invention were tested.
Compound 5 (3-carboxypropyl 5-amino-4-oxopentanoate hydrochloride prepared according to Example 5)
Compound 9 (5-carboxypentyl 5-amino 4-oxopentanoate hydrochloride prepared according to Example 9)
Compound 10 (7-carboxyheptyl 5-amino-4-oxopentanoate hydrochloride prepared according to Example 10)
Compound 12 (9-carboxynonyl 5-amino 4-oxopentanoate hydrochloride prepared according to Example 12)
Compound 14 (11-carboxyundecyl 5-amino 4-oxopentanoate hydrochloride prepared according to Example 14)
Compound 15 (15-carboxypentadecyl 5-amino 4-oxopentanoate hydrochloride prepared according to Example 15)
The following compounds were used as reference compounds.
5-ALA hydrochloride (ALA)
5-ALA hexyl ester hydrochloride (HAL)
Stock solutions of the above compounds were prepared by dissolving them in DMSO to a concentration of 100 mM. The concentration used in the experiment was obtained by diluting the stock solution with PBS or cell culture medium.

Cell culture and treatment with cellular compounds and references WiDr cells from primary adenocarcinoma of the rectal sigmoid colon were treated with 10% fetal calf serum, 100 U / ml penicillin, 100 μg / ml streptomycin, and 1% glutamine In RPMI 1640 medium (Gibco) containing Twice a week, cells were split 1: 100 and maintained at 37 ° C. and 5% CO ₂ in a humid environment. To perform the experiment, 5 × 10 ⁵ WiDr cells in 2 ml of the medium described above were added to each well of a 6-well plastic tissue culture plate (Nunc) to ensure proper attachment to the substrate. At 37 ° C. and 5% CO ₂ for 48 hours. The cells are then washed twice with serum-free RPMI 1640 medium followed by 0.001, 0.003,... Of the above compound and reference in duplicate in 2 ml fresh culture medium. Added to wells appropriately diluted to final concentrations of 01, 0.03, 0.1, 0.3, and 1 mM. Only 2 ml of fresh culture medium was added to the two wells. These untreated cells serve as controls. Cells were incubated in the dark for 4 hours at 37 ° C.

Dark toxicity:
Dark toxicity, ie cytotoxicity in the absence of light, was measured by MTS assay immediately after the above 4 hour incubation with various concentrations of compound and reference. For ALA hydrochloride and compounds 5, 9, 10, 12, and 14, no cytotoxicity was observed at any of the concentrations tested. For hexyl ester hydrochloride, weak cytotoxicity was observed in the 0.3-1 mM range with a minimum cell viability of 85%. Compound 15 was toxic at concentrations above 0.1 mM.

PpIX formation:
After treatment with the above-described compounds of the present invention and the reference compound, the cells were washed twice with PBS and the substrate was scraped into a solution of 1M HClO ₄ in 50% methanol with a Costar cell scraper. Cell debris was removed by centrifugation. PpIX was quantitatively extracted from the cells with this procedure. The PpIX content in each sample was determined fluorometrically using a Perkin Elmer LS50B spectrofluorometer. PpIX was excited at 407 nm and the emitted fluorescence was measured at 606 nm on the emission side using a long pass cutoff filter (530 nm). Known standard PpIX concentrations were added to the samples at concentrations that increased the total fluorescence by 50-100%. The PpIX concentration in each sample was calculated relative to the protein content in the control cells as measured by the bicinchoninic acid protein assay.

The results show that all the compounds tested are useful photosensitizers in cancer cells, i.e. have the potential to be used for photodynamic therapy of cancer, and all compounds tested are PpIX in cancer cells. It was shown that the concentration at which the maximum PpIX was formed was not toxic to the cells, i.e. no darkness toxicity was observed at such concentrations. As a trend, the maximum PpIX concentration tends to occur at low concentrations of long chain compounds.

Example 22-In Vitro PpIX Fluorescence Study in Rat Bladder Cells 5-ALA hexyl ester hydrochloride (HAL) is an active component of Hexvix®, a commercially available drug for photodynamic detection of cancer in the bladder is there. Research studies also show the use of Hexvix® for photodynamic treatment of bladder cancer. HAL is converted to PpIX in bladder cancer cells and can be detected by its unique fluorescence. Initial work in the development of Hexvix® was performed in rat bladder cells and tissues as a model of human bladder cells and tissues. This study was conducted as a first step to evaluate the potential of the compounds of the invention as precursors of photosensitizers that can be used in the bladder. In such a first step, the appropriate concentration of the compound was established in vitro by comparing the PpIX fluorescence of the compound with that of HAL. Based on the results, a concentration for further in vivo studies is established.

The following compounds were tested:
Compound 4: 2-carboxyethyl 5-amino-4-oxopentanoate hydrobromide (prepared according to Example 4)
Compound 5: (3-carboxypropyl 5-amino-4-oxopentanoate hydrochloride prepared according to Example 5)
Compound 8: 2-carboxybutyl 5-amino-4-oxopentanoate hydrochloride prepared according to Example 8)
5-ALA hexyl ester hydrochloride (HAL) was used as a reference compound.

PpIX measurement in bladder cells:
Rat bladder cells (AY-27) were cultured in culture medium (9% fetal bovine serum, 1% L-glutamine (200 mM), and 1% penicillin (10 000 UI), streptomycin (10000 μg.mL ⁻¹ ). Grown in supplemented RPMI 1640). Exponentially growing cells (AY-27) were prepared at freshly prepared 0.8 mM HAL solution (one tenth of the concentration used to detect bladder cancer in human patients) and at a concentration of 3-15 mM ( See table below) Incubate for 2 hours with freshly prepared solutions of compounds 4, 5, and 8. Control cells received serum-free medium without any test or reference compound. After incubation, the solution or medium was discarded and the cells were rinsed twice with ice-cold PBS. PpIX was extracted from the cells using an ice-cold lysis extraction mixture consisting of ethanol / DMSO / acetic acid (80/20/1, v / v / v). The cell lysate was centrifuged (400 g, 10 min, 2 ° C.), the pellet was crushed and the suspension was sonicated for 15 min before centrifuging. The fluorescence signal of PpIX was measured with a Perkin-Elmer LS 55 spectrometer (Perkin-Elmer, Beauconfield, UK) and expressed as a fraction of protein content. The fluorescence intensity at 635 nm in each sample was reported for a calibration curve established using PpIX (Sigma-Aldrich, France) diluted in the above extraction mixture. PpIX concentration was expressed relative to protein content. Briefly, a lysis buffer mixture (1 mM EDTA, 1% Triton X-100, and 10 mM Tris-HCl; pH 7.4) was added to a frozen cell dish along with a 500 mM PMSF (antiprotease) solution in DMSO. . The lysate was kept on ice for 30 minutes and centrifuged at 15000 g for 20 minutes at 4 ° C. The protein content was then measured against a BSA calibration curve with a Biorad DC protein assay kit (Bio-Rad, France) based on the method developed by Lowry.

All experiments were performed on 4-5 copies under subdued light. Cytotoxicity was assessed by the MTT test for concentrations of compound> 1 mM. Exponentially growing cells were incubated with the above freshly prepared solution or medium in a 96 well plate for 2 hours. After incubation, the solution or medium was discarded and the cells were washed twice with PBS. 50 μl of MTT (2.5 mg.ml ⁻¹ ) was then added to 150 μl of RPMI serum free medium per well and incubated for 3 hours. Absorbance was measured by dissolving formazan crystals in 50 μl DMSO. Absorbance was normalized to that of control cells.

  It can be seen from the table that the HAL used as a reference produced approximately 304 pmole of PpIX / mg protein with an acceptable cytotoxic level of 15%.

  Compound 4 induced significantly lower PpIX concentrations compared to approximately the same concentration (1 mM) of HAL. A PpIX concentration almost half that of HAL was obtained at a concentration of about 6 times (ie 5 mM). At high concentrations, cytotoxicity was induced.

  Compounds 5 and 8 induced comparable concentrations (ie, 1 mM) and PpIX concentrations similar to HAL at 5 mM. The level of cytotoxicity was also comparable and allowed at 1 mM. Thus, compounds 5 and 8 are promising candidates for use as precursors of PDD and PDT photosensitizers in the bladder.

pH experiment:
The bladder is sensitive to low pH, while the compounds of the present invention (and generally ALA-esters) form pyrazines at high pH. Thus, a solution of a compound of the invention should not have a pH that the bladder cannot tolerate. The effect of the test compound on the pH of the medium was tested by adding the compound to RPMI 1640 medium at concentrations of 1, 5, and 25 mM followed by measuring the pH. It was found that 1 mM compounds did not change the pH of the medium, while 5 and 25 mM compounds changed the pH from 7.5 to 7.1 and 5.5, respectively. By plotting the data, it was found that 15 mM compound would have a pH of 6.0 by interpolation. Below pH 6, adverse effects (such as contraction) in the bladder may occur. 15 mM is well above the expected concentration of 10 mM for in vivo studies (based on experiments with HAL and the process that 10 times the in vitro concentration is used in vivo).

Claims (15)

A compound of general formula I, or a pharmaceutically acceptable salt thereof.

[Where:
R ¹ represents a hydrogen atom or an optionally substituted alkyl or cycloalkyl group,
R ² may be the same or different and each represents a hydrogen atom or an optionally substituted alkyl group;
X is a linking group. ] The compound of claim 1, wherein the —X—CO ₂ R ¹ moiety is hydrophilic. The _-CO 2 ^{R 1} group of the _-X-CO 2 ^{R 1} moiety is a hydrophilic compound according to claim 1 or claim 2. 4. A compound according to claim 3, wherein R < ¹ > is hydrogen or a short linear or branched alkylene group, preferably methyl, ethyl, n-propyl or isopropyl.   X group is a linear or branched alkylene group, cycloalkylene group, arylene group, or aralkylene group, each of which is one or more non-hydrophilic substituents, preferably halo, nitro, And optionally substituted with a non-hydrophilic substituent selected from and aryl, wherein the aryl is optionally substituted with one or more halo, alkyl, haloalkyl, alkoxy, or nitro groups. 5. A compound according to claim 4. X group is optionally substituted linear C _1-4 alkylene group, optionally substituted branched C _2-6 alkylene group, optionally substituted C _5-6 cycloalkylene group, optionally substituted 6. The compound according to claim 5, wherein the compound is a substituted _C6-12 arylene group or an optionally substituted _C7-15 aralkylene group. Linear C _1-2 substituted with an unsubstituted linear C _1-4 alkylene group, an unsubstituted branched C _2-6 alkylene group, or one or more halo or aryl groups The compound according to claim 6, which is an alkylene group. The compound according to claim 1, wherein the X group of the —X—CO ₂ R ¹ moiety is hydrophilic.   Said X group is interrupted by one or more heteroatoms, preferably one or more oxygen atoms, or one or more hydrophilic substituents, preferably hydroxyl, thiol, carboxyl, carbamoyl, ester, 9. A compound according to claim 8 which is an alkylene group which either bears an amine group. R ¹ is an unsubstituted linear or branched alkyl group containing 4 to 10 carbon atoms, or an unsubstituted cycloalkyl group containing 3 to 6 carbon atoms, or optionally substituted The compound according to claim 9, which is a C _1-2 alkyl group substituted by another aryl group. A compound according to the preceding claim, wherein each R ² represents hydrogen. The compound according to claim 1, which is a compound selected from any of the following, or a pharmaceutically acceptable salt thereof.

  A compound of formula I according to any one of claims 1 to 12, or a pharmaceutically acceptable salt thereof, together with at least one pharmaceutically acceptable or cosmetically acceptable carrier or excipient. A composition comprising a salt.   13. For use in a method of photodynamic therapy or diagnosis, preferably for the treatment or diagnosis of disorders or abnormalities of the external or internal surface of the body in response to photodynamic therapy or diagnosis. 14. A compound according to any one of claims 1 to 13, or a composition according to claim 13.   The method comprises a cancer (eg, bladder cancer, colon cancer, or stomach cancer); an infection associated with a cancer such as a viral infection (eg, human papillomavirus, hepatitis B, or Epstein Barr virus); a viral, bacterial, or fungal infection 15. For the treatment or diagnosis of (eg, Helicobacter pylori infection or acne); or a non-cancerous condition such as inflammation (eg, inflammatory acne, colitis, or infectious dermatitis). Compound for use in.

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